Originally Posted by paulo_becas
If you don't like it don't buy it
The problem is that people may not be aware what they are buying here. There is a major difference in regards to whether it is working with the HID or the PS/2 protocol. I know it won't work with other HID devices like keyboards etc., but many modern mice does not support PS/2 protocol, only USB HID and thus they might not work here. It is fine if it only supports PS/2 protocol, but buyers should know in advance.
Since you have still not provided a clear answer on this, I can only assume that you did not develop the product yourself, but maybe just did the PCB layout based on someone else's schematic and code (there are many of these designs around and I built one for myself using one of these public designs).