I remember having an issue with the non-gog version where I was trying to get a gamepad to work but I didn't have enough buttons on it to bind every single button in the options menu to it. It didnt let you skip buttons or use a combination of keyboard/gamepad, it was either your gamepad had enough buttons or you couldnt use it.

Was this fixed?

Does not look like it. You need at least 10 buttons, not including the directional pad which cannot be remapped. This means you need the equivalent of an old non-analog Playstation 1 gamepad or better.

There are 14 functions in total, but the last four (right menu, left menu, select, cancel) can be assigned to the same buttons as the first 10 functions without problems. Being able to assign select/cancel separately from other functions is great and I wish more games did this.

It's a bit of an annoying defect that it's got to be all or nothing for the controller. I have an 8-button controller, which is plenty for everything that's needed.

I got around it using JoyToKey, though there are other similar programs that do the same thing.

I was able to map my 8 button gamepad fine...

I use a Logitech F310, set to Direct Input, and it plays La Mulana just fine.

What gamepad are you using?

Thanks! This bolded bit of info was extremely helpful.