...To add to my first comment: In that same hallway level, I encountered a glitch where the initial bounce pad launched the ball over the top of the entire setup. I didn't try to enter the hallway from that height, but it's certainly possible.
In addition to the comments about the shadow, the perspective often makes it difficult to tell whether your momentum is forward or backward. This is most noticeable in the narrow blue hallway with the row of yellow pads, since that level requires precise control. (Adding level numbers is also a good idea, since that's a more convenient reference than a description of the level.)
It would help if there were an option to auto-buy repellent after every round. As in, click it once, and then it automatically deducts $399 and gives you repellent between each round. Maybe charge a subscription fee or raise the price for auto-buy or something to balance out the convenience.
Every Crush the Castle game I've ever played, on any site, on any computer, always has abysmal lag and load times. That seriously can't be that hard to fix.
Reading the comments, it looks like other people did the same thing on level 30, and it didn't work for them. Odd, but apparently the same setup worked for me - or it just glitched me through.
In the tutorial, you said you need every item to complete every level. I finished level 30 without using the Block or Puller Bot at all.
Screenshot: http://i800.photobucket.com/albums/yy281/karasugd/electricbox2.png
For the 6000, if you have EVERYTHING, then trying this should help. Right from the start, hold the spacebar down. Do NOT touch your angle. Hold it until you get to 200mph, and let go. Keep tapping the spacebar so your speed is constantly hovering at 197ish, and still keep your fingers off the arrow keys. Do that until you run out of fuel; the best I got was a max altitude of 207, distance about 3250, with my speed naturally dropping. When your speed gets to 40, dive forward until it's at 100, then pull back up at a very low angle (try to keep it at 11%; 9 is an ideal, don't go any lower than 7 or higher than 14) until your speed reaches 35. Keep diving and pulling back up until you get to 6000. On the second dive, pull up at 80mph; on the third, 70; on the fourth, 65; and for every dive after that, pull up whenever you think it's best.
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I will try adding the shadow soon, I think that will make it easier to tell what direction you're going aswell. Thanks for the advice!