Fri May 06, 2016 8:33 am by lax
Re-reading the error messages you posted, it says the issue is within Microsoft-provided Regex code while reading XML, and says "Attempted to read or write protected memory. This is often an indication that other memory is corrupt."
That is completely bizarre and unexpected while starting ISBoxer. I would say either you need to explicitly use "Run as Administrator" to launch ISBoxer, or you may need to disable some security software (or some other software that is stopping ISBoxer from reading the files but again we have NOT seen this error before), or you may need to reinstall Microsoft .NET Framework 3.5 with Service Pack 1..... otherwise you have some unknown problem on your PC.