Hello, @paolo! We have just released the new Magerit Web Updater. Now, you can update your modules at ease and upload the wavetables to Laniakea without downloading any updater. Just go to: https://magerit.es/downloads/?lang=en . You will need to have Chrome v89 and above or Edge v89 and above.
Remember that the format of the waves must be in .wav. The file must have 64 waveforms and each waveform must have 256 samples. You can take a look to the following site to download free wavetables: https://waveeditonline.com . You can also create, explore and edit wavetables with the following app (it is an open source app, so it is free): https://synthtech.com/waveedit
Have a nice day!
David from Magerit