ok i see now. the current room node is a variable i created in the blueprint of type integer. the rooms node is a variable as well but it is an array and its type is actor. to get those two nodes you first need to create the variables. to create variables look on the left side of your screen and you will see a scetion called variables just click the plus sign on that tab and it will create a variable, then with the variable selected in the panel on the left you can modify it in the details panel on the right. the two show thus far are get nodes. to get those drag the variable onto the graph and a window will popup asking if you want to get or set, select get. the last node is a set node for current room, to get this one drag the current room variable to the graph but unlike before when the window pops up select set. you could also right click the graph and type in set current room to get the same result.
dont worry about the communication as long as it works out right. you may just have to answer an extra question once in awhile