Hello,
Further to Lundin's comment, if your program uses the default allocation for placement of global and static variables, it is possible that zero page RAM will not be utilized. If this is the case, you can gain some additional RAM space by allocating some ot the variables wthin zero page. You will need to use the appropriate pragmas to achieve this.
The memory available for global and static variables will also be balanced against the stack size. If the stack size allowed is over-generous, you might consider its reduction. But you will need to experimentally determine the actual stack requirements of the program for a worst case situation.
Are you using the MCU type that DMR115 was intended to operate with, or a smaller device?
Regards,
Mac