You could use the LCD4Linux webif to change the settings that is giving you problems.
http:// Dreambox IP /lcd4linux/config
Boot your Dreambox without the Pearl frame connected.
I suppose it would work fine, if you just set Picon transparency to "No".
"Yes (32bit)" would give you problems like you described.
You would also need to transfere the DM800 OE2.0 files from the first post in this thread.
Download "libusb Fix fuer OE.2.0 DM800 LCD4linux"
Read the "Read me" file.