1. Can i still use the RV without it while the replacement part arrives?
Short answer yes. but you need a way to recharge the house battery. My solution was a Deltran Battery Tender. the big one (not the maintenance unit) this one has 2-20-70 amp output.. (70 is for jump starting a car) hook it up and it goes into 20 amp mode when the battery is full it goes to 2 amp... NOTE I had to reset it a few times before I got the replacement part 3 days later.. There are many "Smart" Car battery chargers out there.. No need to get the same one I got.. Just make sure it's a "Smart" type.
2. Do i have to use the same model or can i order a different one?
No. Though I did. the reason I did was 2 fold. ONE> When you got the best ignore the rest and the Progressive Dynamics 9100 series WITH optional charge wizard. None better.. Two.. By making a very slight adjustment to my route.. Progressive Dynamics was "on the way" (I went to the factory and got a rebuilt)... (Used to live about 20 miles away). But I'd suggest the PD 9200 (Built in wizard) With or without optional dongle if your converter is a stand alone or the 4600 if it is built into the power distribution panel (Again dongle is optional.. Most do not need it).
3. Is there anything else i should be checking to make sure the new one is not damaged when i install it?
well I'm wondering why the converter works outside the RV but trips breakers inside... It may be the wire that connects the converter to the Breaker or it may be a hot to case short in the converter... Either are easily fixed.