The patches to minimize impact from the usability issue are published at
http://help.x-cart.com/index.php?title=X-Payments:Troubleshooting#Duplicate_charges
Our techs are provided with instructions about the issue, too. The patches are provided free of charge, but if someone wants them to be applied by our techs we may charge them according to SLA of our technical support service.
I don't think patches are hard to be applied and everyone should be able to apply them without hiring someone.
How to apply patches -
http://help.x-cart.com/index.php?title=X-Cart:To_apply_a_patch_manually