So here's a feedback especially on time trials.

+upsides :
* levels are pretty neat designs taken separately (as they make less sense together), and proposing various game mechanics encountered during main game for the most
* this time trial mode is slightly reviving the interest of the title once finished even though the number of levels could have been higher to become a real second game inside

-downsides :
* accuracy to get gold medal is somehow broken by gameplay (mainly the mouse click locking poor system) and also large amount of luck it requires to get alignments/angle/timings right
* music design is giving headache, especially when you have to restart often in order to reach a specific medal achievement ; in the end, better played without !