The HPS40 and HPS50 share the same signal processing hardware and software, so despite some differences in the PCB layout, the calibration procedure for HPS50 should be exactly the same as for HPS40. Although the PCB in HPS50 has a little different layout than in HPS40, yet the analog front-end with all the calibration CVs/RVs is exactly the same in both scopes (and even for elements that are laid out differently ALL the markings agree).
Please compare the schematics and PCB layouts:http://www.velleman.eu/images/tmp/hps40 ... screen.pdfhttp://www.velleman.eu/images/tmp/HPS50 ... c%20V2.pdf
I don't quite understand the idea of support forum where one and only answer is "please contact our service center". It is pointless. You state that the device is "Designed By electronics enthusiasts For electronics enthusiasts", while on the forum you show completely no support for your fellows electronics enthusiasts. If the motto would be true, you should make the project Open Source, but in real You even don't agree to publicly release a binary version of device firmware! You also openly admit that servicing of these units in your service would exceed the unit value - crazy!