Hi, Not sure how much support you will get trying to run this $%%?. You could borrow a machine for the duration of the event or even hire a smaller console(hedgehog) if budget allows.
The short answer to your question is that we have to test and support everything we deliver on all platforms that we support. Adding testing/troubleshooting for XP (which not even Microsoft supports) would slow down ALL releases and make everything more expensive.
If you really must use XP the last version we support in 2.7.0.
Currently we support the following Windows OS's: Windows Vista (32 or 64 bit) Windows 7 (32 or 64 bit) Windows 8 (32 or 64 bit) Windows 8.1 (32 or 64 bit) Windows 10 (32 or 64 bit)