Alivio RD-3100 sgs rear derailleur : 2 fitting issues

part 2.
2 things I want to point out when fitting : Shimano Alivio RD-3100 SGS Rear Derailleur.
I will do a 'full fitting' of this derailleur later.
For now I want to point out 2 things new to me that Joe Public might wonder about.
my knowledge : 2/10

[@mdforhad-wk1zo]

Due to bent dropout and unsupported cog

[@alexmac9868]

super materiał. Dziękuję.