I have made general usb keyboard working on my N800. (a otg usb adapter and host mode on N800)

I also turn on the mouse cursor by commentting out the Inherits=xcursor-transparent like this:
[Icon Theme]
#Inherits=xcursor-transparent
at /home/user/.icons/default/index.theme.

But my logitech G1 still cannot work on my N800.

Is there any problem?

Search! Try searching in titles only for, say, mouse support.

Sorry, I think these threads are not appropriate for a newbie.

Could you provide a howto or tutorial?

I think there are two problems for using mouse: 1, make cursor visiable and 2, make mouse button effective.

You could check the wiki, there might be something there. If not, you probably should work through the stuff in this thread in particular until you get it to work (or until you get stuck, then ask specific questions), and maybe put what you did, in a newbie-friendly form, in the wiki.

You're right about the issues, though I'd approach them in the reverse order; apps with cursors (like xournal, vnc, rdesktop) could be helpful to check the mouse is working initially. There's some data on changing the cursors (there is a cursor, it's just completely transparent), somewhere, but it seems you already got that? If not in one of those threads, then search around some more. I did that (though not the mouse part) in OS2007, but haven't got back to messing with such stuff since the upgrade.

OK, I've had some success, it's over here.