Puzzle #114: Corral; Crates

I liked the Crates variation when I first saw it on Palmer's blog. I didn't like the red numbers so much though. That's why I preferred the one puzzle without red numbers. Last year's USPC also featured a Corral Crates puzzle without red numbers. So my puzzle also doesn't contain any red numbers.
This puzzle originally didn't start out as a crates puzzle, except the five 17s and the antisymmetric pairs of 7's and 10's on the outside made a valid corral loop very difficutl to acchieve. I constantly ran into the problem of having no possible valid loop when designing. So I tried to switch to a Corral Crates design instead. It did make the opening a bit harder. I edited out a harder spot in the middle, but kept the opening in as I had already found it a nice way to make the five 17s work in earlier design attempts.

Rules for Corral

In this puzzle there can be isolated loops on the inside the bigger loop. These isolated sections always form a 1x1 square. Different loops don't touch eachother, not ever by a corner. These isolated loops block the sight of the numbers.

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