The -4way algo does seem to work alright and successfully generated a few coins within a day or so.
It seems there something wrong with the padlock code for the VIA Nano, at least in 64bit mode.
I dont think it supports 64 bit mode, it is only coded for the via c7 atm. the C7 doesnt have 64 bit support. It should work compiled for 32 bit mode on the nano even if it is a 64 bit os. If you want to get involved, the nano has some extended hash instructions that would be usefull I think to speed it up on the nano. Make a separate sha256_nano module, keep the sha256_via separate for the c7 I think would be best for now.
There may be still some problem with the sha256_via even on the c7 in 32 bit mode. Not sure yet. I am doing a testnet run but no results for certain yet.