Are all of the games in the X series compatible with the Xbox 360 controller on Windows 7?

So you can rebind the buttons on X3 TC and AP?

Yes, in the more recent titles the options menu allows full customization, and even different control layout that you can save and load at will.
You can also do that in the older ones to some extent, but they are more limited in that aspect, so you'll need the help of some 3rd party tool to get a comfortable setup.

Side note:
since those are quite complex titles and a gamepad has a very limited amount of buttons, if you have access to a decent headset, you might want to have a look at some voice control software like VoiceAttack, GlovePIE or similar, which works great with this kind of games and it's also very immersive... you'll be able to assign unlimited command s and/or macros to a set of spoken phrases, freeing you few precious buttons on the pad for the very critical stuff.

Do you know if there is a way to reverse the axes of the throttle or the rudder? When I looked in the Options of X3: Reunion, I only saw an option to reverse the axes of just the main joystick.

Not sure, sorry... I only got X2 installed on my machine at the moment, can't check it

You can definitely do that with 3rd party software if the game won't let you. Take a look at XInput Plus.

https://sites.google.com/site/0dd14lab/xinput-plus

Unfortunately the site is in Japanese but the software is usable. Allows you to completely remap XInput devices and saves the settings for the game executable. I use it for setting up my 360 controller for old DirectInput games, like NFS Most Wanted and Carbon, and the X-Wing and TIE Fighter games, as it then allows both triggers to be used independently instead of sharing one axis.

I found out about it from the PC Gaming Wiki.

Well, I was hoping there was a way to do this without needing a third-party program, but thanks for the info!

http://www.egosoft.com/download/x3ap/bonus_en.php

Try that before trying some third party app!

I don't know if you've got something working for this now but my recent DirectInput mod for X:BtF
( http://www.gog.com/forum/x_series/joystick_throttle_doesnt_work ) could likely be extended to intercept the axis values from a 360 controller and sent inverted onwards to X3:Reunion.

It's not something I really need for myself but I like programming and I'm feeling generous - so if you're up for testing it I'll take a look :-)

Sure! If there is a way to reverse the other axes, I would like to try it! Would this be a mod for X3:Reunion? How would one install it?

It'd be a DLL patch, like how nGlide works. I described it here: http://www.gog.com/forum/x_series/joystick_throttle_doesnt_work/post10

Installation will be a case of 'extract contents of zip file into X3 folder, done' (there'll probably be a quick "edit simple config file" step since you want some options) but it's not an invasive driver replacement or anything like that.

It's late here so can't start now - I'll post back when I'm done.

Sounds cool! Good luck! :)

Thanks. I've done some work on this but I don't think it'll be enough to make X3:R work on a 360 pad like how I imagine you're expecting.

Download here:
http://davidwaltersdevelopment.com/tools/dinput/

You can invert the Z axis which will make LT/RT work the other way. I'm not sure what else I can do though. Do you have the game reading from the right stick at all? There are options for a 'joystick 2' in the UI but I don't know what that relates to.

I tried your mod and I checked the "Remap Slider0 to Z-Axis" option, but it is not recognized by the game. The shoulder buttons LT/RT still don't register. Also, would it be possible for you to add the ability to make the right joystick on the 360 controller work in the game?