I wasn't sure, but I thought that picture was of ice, not gelled fuel. It doesn't look anything like my gelled fuel.. but I didn't want to post without being sure.
I agree that it's necessary to change the filter (or at least remove the bowl and filter and clean out the bowl) regularly. The owner's manual recommends very 50 hours, but I find if I don't do it more often, even in the summer, it's asking for trouble. Again, I think the very small size of the filter on these little tractors comes into play. Probably if the tractor is used regularly or constantly, 50 hour intervals are enough, but in a case like me (tractor has 170 hours in 3 1/2 years) doing it every couple months makes sense.
The Mr. Funnel makes sense, though I haven't gotten around to making the purchase myself. I've never had water problems, but if I did, I'd probably run for it. I do use a fine mesh screen in my funnel per manual instructions and I often find interesting items there. The last "find" was about six dead wasps.