I’ve set it up so in full screen composition mode, it’s a black background with white letters and a white cursor.
I have the regular editor mode setup with a black background with white letters, but the cursor is black and it’s almost impossible for me to see it.
Do you know how to make it white? Is their a setting that I can’t find?
Check in the “Customizable Colors” section of the Appearance preference pane. You’ll find an option for setting the insertion point within the Editor subsection.
Just a general usage note, you should be aware that working this way in the main text editor means that your text is literally white. That can potentially make your text difficult and confusing to work with if. Fortunately when you compile you can (and will want to) strip all colour from the text, in the Transformations compile option pane. That by necessity means you cannot use text colour for any presentation. This all may be fine for your purposes, I just wanted to make sure you knew this was actually white text here, not normal text that is temporarily displayed as white (like Composition Mode can do).
I set the insertion point to white, which made the blinking line part white. I’m talking about my actual mouse cursor to be white. Is there any way to do that?
Do you mean the “I-Beam” mouse pointer? That should be reacting the environment and turning white if appropriate. What OS X version are you using? The regular arrow pointer is not something we have control over to my knowledge, but given its design of having a white outline around a black arrow shape, it tends to work no matter the context.