Apostolictonio, I am quoting what the manual says. It does not say which parameter number the transpose function is on (I couldn't find it anyway) but it's under settings that affect the entire keyboard. (global parameter)
1. Press [EDIT]
The [1] - [8] indicators will blink.
2. Press [1](SYSTEM BASIC) to enter Edit mode.
Now only the [1] indicator will blink.
3. Press [<][>] to select the parameter whose setting you wish to adjust.
4. Press
- [-] to adjust the setting.
5. Press [EXIT] or [EDIT] to exit Edit mode.
My understanding of the manual is that there are parameters grouped into 8 groups. Each group contains different parameters that can be adjusted. Judging from the manual, my guess is you'll find the Key Transpose under group 1, setting 2. If not, keep looking, it'll say E1: Key Tranpose on the LCD screen. You can transpose from -6 semitones to +5 semitones.
Hope this helps.
Oh, if you need a copy of the manual, PM me with your email address, I'll email you the PDF. Or you can go to Roland's website and register your email address with them and you can access the manuals from their website.