First of all I can't thank you enough for pushing a bit more with Bouncenoid! N23 is so cool, it means you are so close to reaching zone 4, given than N24 is a bonus level where you can't die. Now, here are a couple more tips to get you over N23 and further, just in case you try again one day:

• First of all,  all the levels are designed to be finished in one life only and get all the bonus bricks in the process and without using any Extra-boost. Actually at first there was no Extra-boost available, I added this afterwards, to make the game easier. So each level has at least one strategy that works reasonably well without spending many lives. Of course, there is the strategy and then achieving the strategy, which can take some practice. But if you reach N23, you must start to be getting quite good already ;-) But practice directly levels that took you a long time to finish (with "Select a level" menu item), is useful to make sure you have a good strategy for all the levels before you reach the one where you struggle.
• Now specifically for N23:
  • as I said, there is a way to succeed without using any extra-boost (see 2 videos below). But you're right, for very few levels like N23, if you destroy the key boost bricks and you don't have any Extra-boost available, well, you're jammed and have to suicide or force game over to record your score. Which means that you need to collect Extra-Boost as much as you can and save them for when it's absolutely necessary, like for N23 if you have destroyed all the boost bricks.
  • For N23 itself without extra-boost, you launch and go over to the left, then fall on the penalizing brick. Then you press the right arrow to jam the ball to the right, but not going over straightaway: I make sure the ball is not hitting the top and is only bouncing on the bottom brick. Then I move to the right in hardly stopping and the boost brick at the end makes me jump on the next level. Then I go to the left to use the boost brick to get to the next level and same again on the right (video 1). What can also happen is that the first boost brick on the right actually makes you hit the boost brick just above, in which case you bounce up again and touch the boost brick above, which makes you bounce high enough to finish the level (video 2)

Here are the 2 videos showing these 2 different methods:

• As for how long it takes, in a straight line, even with a few lives lost on the way, each level is about 15-30 seconds max on average (some are so much quicker around 10 sec, not counting bonus level where you can pass almost immediately if you don't take any bonus), so reaching level 23 should be about 10 minutes max when you know the strategy for each level. But I agree with you that it's the kind of game that requires some good concentration for some time. Finishing the game is about 20-25 min, but it can also take 1 hour with infinite lives mode if you really struggle with many levels - and provided you don't find yourself jammed before the end.

Anyway, thank you again for trying so far :-)