Re. S-63 for ARM: this is on a to-do list but we have as well the Android which would require another, different approach for the fingerprint and licensing stuff. So not for the day after tomorrow.
Licensing charts from UKHO: yes, this possible for are very reduced amount for the leisure market (ENCs and RNCs) under the condition that you will a) encrypt the charts and b) will not call these "official charts" but just "based on charts released by Admiralty/UKHO".
We are aware that VisitMyHarbor and others are not available for Linux
Going this way would require some infrastructure and upfront spending.
Investigations how this can be done and possible alternatives are under study.
More or less the same story is valid for German (BSH) and French (SHOM) chart sets. The upfront investment hurdle in the case of SHOM is more significant.
In the case of SHOM the ENCs do not cover regions which are important for OCPN users, so raster has to be taken into account. This implies encrypted raster.
The next playground in this context.
There is no risk that we will have a boring time....