Previous purchasers can now
upgrade. Just select the 'Upgrade from v4.3.x' option.
v4.4.1 users, ensure you have patched your cart with this bugfix...
https://bugtracker.qtmsoft.com/view.php?id=38576
- DIFF_53986.patch
- function.load_defer.php_1.18.2.4-1.18.2.6.diff
It fixes the JS/CSS speedup tool (in General Settings), which when enabled will speed up your store.