There is no problem using the software on XP, the vast majority of peopld do so!
This error:
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it said “Run-time error '-2147024809 (80070057)' and then SRCVW32lex routine
utRegExpPropHelper-Invalid or unrecognized expression syntax..."
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is purely caused by an out of date system file (srcvw4.dll) on your computer. Note this file is a common file used by several commercial applications (e.g. Microchip MPLAB aswell as the Programming Editor).
Therefore if you remove all instances of this file from your computer, and then reinstall the Programming Editor 5.0.7 full version (which includes the correct, latest version of this file) you will have the correct version installed on your machine and the error should go away.
It is not an XP problem, it is an installation problem on your particular computer.