Hi, yanpetr!
My module, at 45USD is still one of the less expensive filter modules on the opencart market. I've seen less complex modules priced at 90USD and they obviously have less features than SimonFilters.
Hundred of work hours have gone into this module... I try to accommodate all possible requests by users and have done so on >90% of times...
As for non VQMod support, you are absolutely right. but let me try to explain why I was forced to temporarily suspend support for non VQmod stores:
At one time I provided 4 different versions of /catalog/model/catalog/product.php each for a different version of OpenCart
The problem is that a lot of OpenCart users, who don't use VQmod, already have some sort of customization made to their /catalog/model/catalog/filter.php
That means that, when they replaced their existing version of that file with the one I provided, the store would break down because all their previous custom changes were lost!
With that in mind, I consciously stopped shipping the module with all those different versions of the product.php file and added instructions to the readme1st.txt file on how to do the required changes manually.
Anyone with simple SEARCH and COPY&PASTE skills can do the simple addition of code to the product.php file.
Fast forward to today: I'm on the last steps of, once again, support non VQmod users! :D
Next version v2.7.1, scheduled for the end of this week, will bring an algorithm that will allow the user to automatically add the relevant changes to the product.php and make the module work even without VQmod!
Of course that if the original file is heavily modded (as some stores I have found) the task will be impossible but for more than 90% of my test cases with files the users have sent me, the algorithm works perfectly and the module runs as well as the VQmod version.
Tests look good and I think it will be fully functional with another 4 or 5 hours of work.
Cheers,
Simon