Load Arcy II, and start a new game. When level 1 starts, press S, save your game in the first slot, then quit to DOS.

Now use a hex editor on the file SAVE1.DAT from the main directory. Find hex location 101. Changing its value (which should be 01) to a hex number between 01 and 14 (levels 1 to 20). The save game should now go to the specified level when reloaded