Superocean heritage

[miagi]

Hi, i just received my new superocean heritage, and as flawless a visual replication as it is , i got a problem with the movement stopping after a short time. the funny thing is that every time i unscrew the caseback and putting a glass over it (to keep dust from entering the movement) it will run for a long time. but as soon as i screw back the case it stops within an hour. ... so my question is ; have anyone else had this problem ?

i tried to dremel down the inside of the caseback to create more room for the rotor to spin. and it seems to be working as of now. also is the stem too long when the date keeps changing (two or three days) when screwing down the crown after setting time?

i would like to add that i have been in contact with the dealer and he told me to just send it back for a repair or replacement. - but im a little concerned with sending it back...customs etc.

hope that you mighty fine ladies and gentlemen of this magnificent forum can bring some answers to mind

(did not find anything similar symptoms when searching)