Sorry for the late reply, but I had not enough time yesterday.
Let's start with level 5 (Shvegait).
The backdoor you found is not hard to close. Also, I edited a little to prevent the possibilities to do some other tasks which could be used for more backdoors.
However, I'm still not sure about alternative ways.
For the new level, see here @everyone:
http://de.geocities.com/geoo89/g0s09-2.zipI'd say, if without backdoors, it is harder, or since I maybe underestimate #2, about as difficult as #2.
Also, have you already made a decision for the steelblocks for level 9?
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Now level 8 (ccexplore):
The way you told me per PM is, you're right, the intended one.
Also, the backroute you found is, as you said, easy to close; the one I found too.
If you didn't find it yet I can PM you if you are interested.
About the trick, see PM.
Level 7:
Also here you're right with the intended solution. I did it just a slightly different which caused that I only could save 22/25. Mine is a bit harder and I could avoid yours making the last step 8 pixels high, but maybe I accept it too.
Your 'infamous' first non-timing solution, whatever it is, will of course keep (if I don't make it impossible accidentaly).
Now, solution #4.
I think it would be possible to avoid this way increasing the height of the first or third 7-pixel step by one. And I'd prefer ... - 6 - 7 - 8 - 7, not ... - 6 - 8 - 7 - 7.
But I don't know whether #3 with the advantages would make the backroute possible still.
Nah. It's probably just the "creator's blind eye". When you create a level with a particular solution in mind, you tend to overlook other ones, especially contorted ones that a struggling mind conjures from the depths of, um, something. Remember, I'm still stumped by your level 2 which you believe should be easy.
Well, yes, that might be another aspect.
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For level 4, I actually had a level idea for replace, but it turned out that this wasn't possible. So I have to think of something different.
Thanks you two for your help.