Thanks to another RPG Maker who created a new script I think I have a way to import and export save files for web players. Testing this now. This is in the cheat area ATM. Clicking export will ask you which save file to export. This will save a file. Clicking import select the rev file saved to your system. You then need to refresh, and continue. Select the save slot for the file you exported, your save should be in that slot again. Its not super straight forward, but seems to work. Need to test on Mobile next..