What file versions of ReEnterPBP-18.bas and ReEnterPBP-18LP.bas are you using?

The 18F1320 has 256 bytes of ram, and utilization should look like this.
Code:
PBP's system     26 bytes
DT_INTS-18       26
ReEnterPBP-18    68
ReEnerPBP-18LP   68
                ---------
                188 bytes

User Vars        25 bytes
		---------
                213 total

Remaining RAM    43 bytes
Are your variables in an array?
Are they being specified in a particular Bank?

Do you have "Complex Formulas" in your program ... If statements with 10-15 AND/OR's, or math formulas with lots of parenthesis?

PBP creates extra system variables for complex math or logical conditions.
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