There is probably an easy fix the developer can patch. Game performance issues happen with all games from indie developers to powerhouse publishers, like Blizzard-Activision. The game doesn't run well for the majority of users so patch it.
The developer has been awfully quiet regarding issues. Hello?
Also, one more thing.

Last night, I was playing the game for about 2 hours and it got very choppy.

I exited and realized that my GPU temp had shot up to 64 c (which makes no sense for a 2d game, and no there is no problem with my GPU, either).

I checked NA and it reported that windows was running some sort of assessment program.

ok, so this explains the choppiness of the game, but why the gpu suddenly started running at 100% makes no sense.

Many thanks mg1979, I've never used this tool before but am thankful to learn about something to add to my computer toolkit.

I just want to add to your instructions as I could not get the BES software to work properly with my settings because of a few factors with my setup.

First of all I have a i5-3570K Overclocked to 4.2GHz, running Windows 7 64bit.

MAKE CERTAIN that the executable Eador.exe is NOT set to run with Administrator privileges. If it is the Battle Encoder Shiraz cannot moderate the CPU usage.

To change this simply right-click the Eador.exe in your game path, select the "Compatibility" tab and under Privilege Level untick "Run this program as an administrator".

Make sure to follow the instructions of the original post to get BES working with Eador. Also set the "Sleep/Awake Cycle" under the "Control" menu for BES to the lowest value (4 miliseconds, the default value will cause it to stutter like crazy and your back to square one).

The music is now smooth and the mouse movement is much improved (not perfect, but far far better).

Thanks once again for posting your solution mg1979

This worked for me:

1. In Windows, create a new power plan (Control Panel > Hardware and Sound > Power Options). On the left, there should be a "Create a power plan" link.
2. Choose Balanced, then give your plan a name (I called my "Throttle CPU"), then click Next.
3. Choose the "turn of display" and "put the computer to sleep" options that you prefer, then click "Create."
4. Next to your newly created plan, click the "Change plan settings" link. This brings you back to the display and sleep settings. Click the "Change advanced power settings" link that will now be visible below them.
5. A Power Options window will pop up. Find the "Processor power management" setting, then expand it by clicking the + symbol. You'll then see some other things appear, one of which is "Maximum processor state."
6. Expand the "Maximum processor state" setting. You'll see "Setting: 100%" next to it. Click that, and change it to something far lower (I set mine to 50%). I also went ahead and changed the"Minimum processor state" to 5%.
7. Click OK.

Source: http://www.snowbirdgames.com/forum/index.php?threads/eador-genesis-%E2%80%94-troubleshooting.72/

Either that or run BES as Administrator (maybe it's better, I don't know if Eador was set to run with Admin privileges for a reason). Glad it worked for you, I hope that this, with some changes in the Eador.cfg, can solve the problem for many.

Take notice that you can adjust the slider in BES, for example I can reduce the CPU load of 30% max, if it's set too high the music stutters again (too little CPU power), so you should find the value that suits your PC better.

I suggested to run BES through command line

"C:\*path*\BES.exe" "C:\GOG Games\Eador - Genesis\Eador.exe" 50 --minimize

If you adjust the slider you should remove "50":

"C:\*path*\BES.exe" "C:\GOG Games\Eador - Genesis\Eador.exe" --minimize

this way BES will remember the last value you set.

Good point, mine was set to 40 and was rather ok, I set it to 20, I'll see if it makes a difference.

Thanks digitaljc; this works perfectly as well. You just need to remember to switch the power profiles once you have finished playing Eador. I found that I could get away with 95% maximum cpu and 5% minimum; though it is probably because windows is controlling how much CPU to give Eador (it isn't really using 95% from task manager it looked more like 60%).

Thinking about it a bit more, I am a little confused as to why this works. If it controls the maximum CPU clock then would you still not have 100% CPU usage in Eador just at the lower CPU speed?

Some Windows guru probably knows what is happening here; nethertheless it still works for smooth playing.

HiPhish's recommendations for solving the mouse lag issue didn't work for me, but after some toying around with the options in the Eador.cfg file I did find one option that greatly improved mouse control (and overall performance) for me: setting "Color depth" to 16 instead of 32 (presumably this dials down the graphics to 16-bit levels). I'll try putting it up to 24 to see what happens, but it might be useful to others who are still suffering from mouse lag woes.

Edit: Still laggy under 24, so I'm sticking with 16.

I made a YouTube tutorial based on Digitaljc's instructions.

Eador Genesis - How to stop lag

Hope it helps. :)

Heh and here I was trying to figure out how to contact you so I could ask you to do a lets play on this game Das :)
Should have known you would be here slightly ahead of me.

After holding firm all these years I might have to finally break down and make you the first channel I've ever subscribed to.

Ubbax
"Do not seek to follow in the footsteps of the wise. Seek instead what they sought" - Lao Tzu

Damn, this really works! Such a simple and elegant solution to the problem. Thanks a lot!

Watched the youtube video. Excellent video! Eliminates the lag almost 100%, only occasional popping from the sound.

I wonder if this would eliminate the popping heroes of mm 2?

Automated fan-made launcher version 2 is released, for those who don't want to mess with the power configuration.

I had the same issue with a laggy mouse, graphics and sound. Throttling the processor's power solved it for me. The previously posted video above by das is it.

I also found that I had to throttle the processor even more than the 50% suggested. I have an i7, and 40% got the game working perfectly for me. You might need to do more or less depending on how beefy your rig is.

*Note, that this is also why multiple instances of the game open will run better. You're just in effect giving each one less processing power

Just like to bump this since it fixed the problem for me, as well, and if anyone else comes new to the game it would be nice to see this near the top of the forums. I have a lightly overclocked i7-4770k, and get the best results setting the maximum processor state to 10%, so anyone with a new 5th gen Intel core CPU should consider starting around there and probably even working your way down. Didn't need to kill background processes, sound, or run in compatibility mode.

Works fine without throttling on my old, ultra low-voltage laptops, though it does run hot. Haven't found a good fix for that yet.

I run the game from the start without trouble and have found none of these issues, but it was soporipherous to wait for all the message windows to show up on hovering. I just turned off enhanced precision and it does make the mouse feel loose, but it indeed bettered time for hovering windows to show up and trail, not worth mentioning in the end, I ll set it back again to enhanced... Now I think I may have a problem, and will have to see what happens if I tweak all these suggestions!