the other day i was at a red light and i had the clutch all the way in and i tried shifting into first...except the shift **** kind of hit a wall and refused to go in...i tried the other gears which worked and after shifting around i finally got it to go in 1st.

also, when i do my redline a day from 1st to 2nd, it seems as though i have to wait for the rpms to drop a bit before i can shift into 2nd gear.


when the car got checked at the dealer, they did say the motor mount was cracked but it was "not urgent"

can anybody confirm that the problem is related to the motor mount? or is it something else?

 

Could definitely be the motor mount. You might wanna get them replaced, it should take care of vibration during idle as well, so if it vibrates while idling (specially when the fans kick in) that's a symptom of bad motor mounts.
However, having issues moving from a dead stop is not too common for bad mounts, it's usually really hard to shift from 1st to 2nd during redline, so it could be something else.

 

check your clutch pedal also. they break. dont bother with a bracket, take it out and weld it

 

A bit more information would be helpful

Model year, mileage, maintenance, any recent work?

Trans can act up if the fluid is old.
MT works best with Redline MT-90 synthetic GL-4
Diff takes Redline 75-90 synthetic GL-5

Edit: Clutch pedal mentioned above can cause a shift issue and is well covered in multiple threads.
Pedal can be reinforced with a bolt on reinforcement or can be welded. If in warranty a broken bracket will be replaced at up to 8 years in NA.

The link below has nice pictures of the issues, various repairs and preventive measures
https://www.rx8club.com/race-roots-1...ations-194975/

 

but the bracket if broken can cause more issues and iirc the replacement is no better. dont waste $ on a bracket, broken/cracking or not yank it out and weld it