Help idenitifying eastern front pictures

[olseer]

My grandfather was a pionier and worked on the railroads. He was drafted in 1941, went to training in Koenigsbrueck, and then went through Minsk and then spent most of the war around Roslavl and Bryansk. He was normally assigned Feldpostnummer 42805.

My mom has several pictures and would like to see if anyone can provide any additional information on what they see within the pictures:

Opa 3: saw mill, probably around Roslavl
Opa 4: probably somewhere in Russia. unsure of the scenery
Opa 5: unknown location
Opa 7: train station somewhere
Opa 8: must be his unit, although we cannot identify my grandfather in this shot