Nice job. I knew you could do it. I think what you're seeing is Chaotic definitely living up to its name. Don't worry. It's quite common to breeze through the first few ranks with little to no problems, but then all of a sudden you start getting stumped starting with the 3rd or 4th rank. It happens to me all the time, so it's not like I'm someone who doesn't ever get stuck on a level. If you take a look at
https://www.lemmingsforums.net/index.php?topic=4894.0, which organizes the packs I have completed, currently playing, and ones I'm thinking of playing, sure, it tells you that I have completed 50 packs, but what it doesn't tell you is how long I've been stuck on some of the packs in order to get to 50 packs completed. Before making the switch over to Neolemmix from Lemmini and Superlemmini and before beating Lemmings Reunion on Lemmini, I say the hardest pack I've completed was Pimolems. Once I've made the switch to Neolemmix, so far I say the hardest I've completed is Lemmings Stampede. I'm currently playing through two packs much harder than anything I've completed, United and Nepsterlems. Right now, I'm about halfway through both packs, but I'm still really far from completing them.
So really, I definitely think you have what it takes to solve levels. Perhaps Chaotic is where you really have to start thinking outside the box. That's a nice solution to Chaotic 14. However, it's definitely more complicated than how I did this level.
I simply dug and bashed underneath both pillars at the top and then built to stop the basher. Where you mined to the left, I did the opposite, once I bashed enough away to get all the groups out to the right. The other groups I digged and bombed in between to get the groups out. With the leftmost group I bashed to the right.