Cant update to version 5.00.6!!

[cobrapilot]

I wante to upgrade to the latest version. I have downloaded all the latest version's. But when I try to install version 5.01.0, it says "you can not instal this version 5.01.0, because you do not have version 5.00.6. So I go online and try to find version 5.00.6, but its not there! Not even on reflex xtr's main web site
http://www.reflex-sim.dyndns.org/reflex-sim/shop/catalog/default.php?cPath=21&osCsid=76a482f7d06ed967a549238eb2962cd2