Homemade TM1 reports can get quite convoluted and users might get a hard time updating them as it is difficult to tell where some TM1 formulas are pointing to.
The excel formula auditing toolbar can be useful in such situations.

AsciiOutput can help tracking what values are being used during execution of your TI processes.

use:
AsciiOutput('\\path\to\debug.cma',var1,var2,NumberToString(var3));

Keep in mind Asciioutput limitations: