-You should probably lower the layer 2 spikes so you can see the very tip of the spikes. That way they don't just crush you when you're running blind.
-Also I think 1 arrow at the beginning is enough to tell you where you need to go; 10+ of them may not be necessary.
-From 0:20 to 0:28 you may want to introduce some obstacle other than just layer 2 spikes to keep your level fresh. Perhaps have a line guide with a buzzsaw or something to keep the player on their toes.
Overall, okay first room, but you could benefit from some small changes. Otherwise it'd kinda look like a Wendy Koopa castle edit.
-Some cutoff shown between the pipe and the end of the ledge on the left side when you start the room. You may want to move the pipe one tile to the left.
-There's also an incorrect ledge tile below the first Ball And Chain. You will want to use the correct ledge tile for this, shown here.
-The 2nd Thwomp kinda glitches a bit because there are too many sprites on screen (the Ball And Chain tends to take up a lot of sprites for some reason) so you may want to consider either lowering the amount of Podoboos on screen or employing a patch that helps you with onscreen sprites.
-At 1:11 you may want to consider lowering the 3rd Ball And Chain sprite or just remove it entirely because it poses no real threat to you.
-5th Ball And Chain also glitches out for the same reason as the aformentioned Thwomp from before glitched out.
-Lower the 7th Ball And Chain as where it is currently positioned, it also poses no threat to you.
-There's also a couple of incorrect ledge tile near the 8th Ball and Chain. Again, you will want to consult the link I provided for the aformentioned previous ledge tile error.
-After that 8th Ball and Chain, the bowser statues can glitch out because of too many sprites on screen at once. The Ball And Chain is also a problem here because while you can't see it right here, it's still technically onscreen because it's loaded in the game's memory. -As well, there is cutoff here as well, as there's no end to the ledge you have introduced near the last couple of bowser statues. You can literally just jump right through the ground and skip the escalator bit entirely. You may want to have a "Solid Left And Top Ledge" here for this part.
-As well, you may want to have an escalator end tile for the top too as it's missing.
-The final Ball And Chain glitches out for the same reasons why the bowser statues were glitching out.
-I find it odd that the color palette for this room was vastly different from the color palette in the first room. Unless there's some sort of theme for these rooms. Maybe it might just be my artistic senses speaking to me but maybe there should be more consistency here with these rooms in terms of palette. This one's up to you though.
Overall, the 2nd room is decent. You may want to fix some redundancies and some small ledge erors and cutoffs. These are all just small problems that are easy to fix. The big and complicated problem however, is the fact sprites can glitch out if there's too many on screen. Like I said with the Ball And Chain segments, it may be worth investing into a patch that helps you with the onscreen sprite problem (dont know what it's called but i think someone else could help you with this). Failing that, you could cut down on a few Ball And Chains in this level.
-If you intend on using that invisible coin block near the start as a platform, then I suggest changing it to a cement block or an actual block, since there's no reason for it to be invisible.
-You may want to replace the bridges with solid castle blocks since they are kinda cutoff. Or if you want to use the bridge tiles, then I highly suggest connecting each bridge end to something, like stone blocks or something so that it looks nice.
-You may want to mess with the color palette in this room since the jumping bowser statue's coloring looks real wonky.
-You may also want to change that pipe at the end to a door since it looks really odd that you enter through a pipe and appear out of nowhere in the next room.
Otherwise, I don't really have anything else to say about this room other than introduce some obstacles that'll give this room some fresh new feel since a lot of the jumps kinda feel samey in this room meant for parkour. Also my comment for the previous room's color palette also applies here.
I've got nothing to say about this room in particular. It feels like a "pick a door" room, really. Although I did just say I have nothing to say about this room, my comment on the previous two room's color palette still applies here.
-The color palettes used in this room are really questionable. I highly suggest picking more fitting colors for this room. The green/orange castle walls, and the gray lava really don't go together very well.
-Although it's far easier to get to safety before being crushed than the first room, I'd still have the crushing spikes visible from the start.
-You may want to place the 3up moon somewhere where it's far more well-hidden. These are special, so they should be rewarded far more cleverly than just being thrown out in the open.
Not much else to say about the room honestly. But please I highly suggest fixing the color palettes for this room. It's a pretty serious issue.
Skipping the Pick-A-Door room, we've got this room. This room... is literally Room 2 of Iggy's Castle, barely edited. You may want to straight up gut this room and start this room from scratch entirely, and introduce your own ideas here. I can't help improve this.
-You may want to lower the ground because it looks kinda odd from a camera perspective to have half of the level be just dirt.
-This is the final room, and I'd have to say 950 seconds is a bit much considering you finished with 508 seconds on the clock. I'd personally drop the timer to 600 seconds because that's way too much time. Maybe 700 if you decided to include a boss. 800 if said boss was Bowser himself.
Nothing else for me to say here, so I'll just skip straight to my final thoughts.
Not a terrible level outside of the 6th room, but could use some improvement. The 2nd, 5th, and especially the 6th room
needs changes. You may want to consider renaming the level as well, or introduce more layer 2 spikes throughout the level, as outside of the first room, the level name doesn't really fit the rest of the level. I outlined my thoughts as best and respectful as possible. Feel free to take them into account.