Hi ! I'm the same and I have found some ways around the problem.

First off you can use a keyboard mapper to remap your numpad to the perform keys (eg. 1 will be Q, 2 will be W etc ...). I recommend Key Mapper, as it is the only I have seen that uses the numpad. When you're done with it, go to Mapping, select Export As Registry File, go to the selected folder and execute the file, then relaunch your computer. The annoying thing is that you will have to undo the changes in Key Mapper, export as registry file again, load again and relaunch.

I have another way that I prefer, using AutoHotkey. First download and install the program. Then, download Notepad2. In any folder of your choice, click right and in "new" you should be able to create a AutoHotkey Script. Create it, name it however you want, then go to Notepad 2 and open the script.

In there, enter this
Numpad1::,
return

Numpad2::;
return

Numpad3:::
return

Numpad4::k
return

Numpad5::l
return

Numpad6::m
return

Numpad7::i
return

Numpad8:: o
return

Numpad9::s
return

NumpadDiv::T
return

NumpadMult::y
return

NumpadSub::b
return

NumpadAdd::X
return

Numpad0::S
Return
(I added a space before the "o" to avoid the smiley but there shouldn't be any)
My perform keys are bound to , ; : k l m i o p so change that to match your own perform shortcuts. I linked /, *, -, + and 0 to the accidentals but That placement is less than ideal. They are the last 4 one that you can change.

Before closing, go to File>Encoding and select UTF-8, then save. You just have to launch the script now !

To end the script, got to your toolbar > Display hidden icons. There will be a green square with an H. Click right on it> Exit.

I hope that helps ! If you have any questions or need help, I'll be happy to explain in more details ! :>