Thank god you went with grid-based movement; it's a pain in the ass to navigate pixel perfect tiny hallways with free movement. This game looks like it has some cool mechanics to spice things up later on judging from your preview, but I never got to see them since the portal level was so random and time-wasting that I quit after a minute or so of wandering aimlessly. I think the game would be much better off if you cut that level.
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the portal level was to introduce you to portals :) I tried to make it a bit challenging without distracting you with a bunch of other mechanics. I tried to keep it from becoming too frustrating, at least in the first few levels (I did get a bit devious later on), but I didn't spend enough time fine tuning them. Probably, after voting is done,I will redo the levels a bit. BTW, if you take a systematic approach at the portals, you will reach the exit in a maximum of 43 jumps, as little as 3 jumps once you know the correct portals.