For some reason I'm unable to purchase items in game, yes I went to my settings, enabled it and enabled it in my game settings too. However its still giving me the message 'Steam overlay must be enabled to purchase energy, Please ensure that 'Enable steam community In-game' is checked in the steam "In-game" settings, then restart the game. Could someone help me fix this issue?
Another way to accomplish this is purchase through the SK website.
If use steam to log into the website, then click on the support tab in the top right, you should end up here: http://wiki.spiralknights.com/Support_Portal
Then click "Buy Energy", you should now be here: https://billing.spiralknights.com/billing/shared/select_type.jspx?choice...
That should get you the same results rather than trying to hassle with the in-game things.