I have just started usking my N900 as a sat-nav while cycling. It is safely encased and mounted in one of these (a good bit of kit, by the way) but this means you can't access any control save the touchscreen and it's a little heder to see the screen. Now, this isn't a problem as using simple brightness app I can whack the diplsy up to full brightness and set keep display on and all is well. However, being a lazy sod, I was wodering if it would be possible to edit the .desktop for Marble to automatically change these settings before firing up the app. Would I need to craft a script and call that?

IMO the best way is to make your own widgets (QBW) or .desktop files that do the tasks you wish.

Near as I can tell, the OP is asking specifically for how one can launch Marble with various settings/options set to different states. Which really boils down to "can you toggle Marble's option/setting X with a command line parameter or config file" (since .desktop files just run the invoking command the same way a shell would/could).

I don't have that answer, but to the OP I recommend looking at the Marble documentation itself, or asking in the Marble thread, the question above, since any options you can pass to Marble when invoking it on the commandline can be pasted directly into the 'Exec' line of the .desktop file.

Not exactly. These are system settings he wants to change, not marble settings. I believe it's doable, by writing to the correct sysfs nodes/gconf keys via the exec line or a shell script.

Oohhh, yeah, upon rereading his query I think you're right. He wants the Marble desktop app launch to automatically set the device settings. I stand corrected.

Okay, well, that's a bit easier then. TomJ, what settings exactly do you want to have set to what values? Most of the N900's device settings can be changed from the command-line fairly easily, and thus by extention from within a .desktop file.

Or like the sixwheeledbeast said, there's also the Queen Beecon widget, which might be easier to use for this purpose.