Thank you.We were over 3.5t when we went in 2018. Avoided go box issue & went through Switzerland- go to office at border & buy a document that allows you to travel in Switzerland- we only camped one night as very expensive. We went to Slovenia initially only to see lake bled so only allowed 3 days but Slovenia was lovely & we ended up staying 2 weeks! Into Croatia- just follow the road down the coast don't use motorways unless you go to national park (we'll worth a visit!) Plenty of drop.in camp sites & Aires all down the coast next to the sea. We didn't have insurance for Bosnia & NO you can't buy it at the border - we tried!! We ended up catching the drive on/off ferry across to the island, drove to end of island which connects with the mainland and then on to dubrovnik. The islands were lovely & well worth a visit, ferry was about £35 at that time.