Is "Makarna peynirli yiyorum." accepted?
Nope. Remember, modifiers always precede the things they modify. "which pasta?" -- "pasta with cheese"
Otherwise it is an adverb and wouldn't make too much sense with this verb tense. :)
Wait, but there was definitely a sentence like 'Çorbayı tuzlu yiyor'. How is this different?
The rules change a bit when we're dealing with a specific/direct object (i.e. accusative case). I made an attempt to explain this HERE.
I couldn't find an official source, so I did my best :-)
So my sentence above would mean "I am eating the pasta cheesy"? (Cheesy on the way I'm eating) Haha :)
why does the order change so much with almost the same translations?
I made a long post about this in a similar sentence HERE. Maybe that will help explain things :-)