I'm having the problem that the mouse movement in the game as well as in the main menu isn't as smooth as it should be. I'm not sure how to describe this, but especially when I move the mouse slowly from A to B, the cursor or cross hair seems to skip or jump a lot during the movement.

This is a problem I have experienced before in a few other older games. Does anyone know what could be causing this? Is there some kind of setting or patch to fix this?

This game is awful, almost unplayable.
You cannot aim at an enemy, because the pointer "jumps".
And every time you fail a mission, you must go back to main menu, and load you current mission again.
I regret I bought it.


Edit.
As a test, I took the game from another "source", and it plays smoothly, with no bug at all, with multiple languages too.

Which version were you running with that game from "somewhere else"? :)
With my retail on 1.0 I totally can't play when inside rooms, because visuals would be to sluggish.
This issue is finally fixed in 1.2 which however introduces that mission reload bug. And 1.3 will not change anything on this matter. Same for the GOG version. So how did you do that? :p

Haha I guess you leave me no choice ;D
I'll try and go for that one! :)

if you continue to have issues with the mouse lagging on IGI 2 Covert strike, try replacing your current igi2.exe version with one higher than 1.3. You can get many versions and some other awesome stuff on this site:
igi2isfkinder.weebly.com/igi-2-stuff.html

Enjoy!!

I have the same problem with the game.
The mouse is lagging en skipping al the time, when I want to restart a level I have to go back to the menu otherwise it wil get stuck on a black screen with the last textures the player has seen. Because of these problems the game becomes unplayable. I tried it on my other computers but ran in to the same problems over and over again. I tried to patch the game but no luck with that either. It's like the crosshair is moving on a grid, also when I try to launch it from GOG Galaxy the screen gets massive, I have to start the game from it's installation folder in compatible mode with Windows XP (S3).

Does anyone found a solution yet?

Go to this site:
igi2isfkinder.weebly.com/igi-2-stuff.html
Download Patch 1.2 or IGI-2 v1.2, then copy & paste into your IGI 2 folder.

By default, this game is running at unlimited framerate, which causes the cursor jump from A to B when entering all the houses in the game. You can't make it run at 60fps, even with Vsync enable (in Graphic Control Panel). Patch 1.2 makes the game to run at 60fps, causing the game not run smooth as you expected (you know, because of vsync) but it will fix mouse movement issue.

Actually,I kinda found a Solution for this and there is a way make it run at 60fps locked by using RivaTuner Statistics Though doubt its permanent but the difference is noticeable and it worked for me.

See if this method helps you out.
gog.com/forum/i_g_i_2_covert_strike/possible_mouse_fix

Yeah, I found that works too. I run at 80fps lock btw.

I've been using dgVoodoo 2 to play IGI 2 following a recommendation from PCGamingWiki. It fixes the mouse look stutter and makes the game perfectly smooth during gameplay as it should be.

The bug related to reloading missions is still there, as well as some weird texture "blinking" which also appeared in the vanilla GOG version.