I guess you have some problems with CSTARTUP files.
In other words, you should adapt the start-up code for your board.
Please check 6812RLM.ASM, 6812RLP.ASM, and 6812RLS.ASM files
under C:\\bipom\\devtools\\MicroC\\Lib12 folder.
As minimum action you have to uncomment RESET vector (6812RLS.ASM)
*
* DDS MICRO-C 68HC12 Runtime library - Suffix file
*
?heap EQU * Heap memory goes here
* For stand-alone ROM system, uncomment the following
ORG $FFFE Position to reset vector
FDB ?begin Set start address
*00000