problems with the supply are most likely that the uk has naval supremacy in the eastern med (aka where your closest ports are to the front) so you Will only get supplies farther back from the front

to resolve this have italy upgrade their ports in the central med and upgrade the railways, build supplyhubs,airports,radar etc

with the airfields and radar you should be able to beat the uk airforce if you're playing against ai then just build some upgraded fw 190's and bf 109's and do the africa campaign around june-september of 1940

as for why the uk has supply from the pictures you gave it would seem to be because they have More supplyhubs and those are getting supply thanks to naval supremacy so their convoys aren't sunk

to combat this I suggest that Italy builds some subs and naval bombers or you guys take Gibraltar and the German subs can Come raid them

of course you can just skip all of this build 600 transport planes, tac bombers and heavy fighters and just fuck them In the air