Entries in your CSV file need the following syntax:
VGC id,"Name","Platform","Notes","Cart","Box","Manual","Other","Purchased Price","Purchased Date","Added",
Comma seperated fields, text in quotation marks, line above must be first line. Sample line:
"94523","007: Everything or Nothing","Game Boy Advance [JP]","","Yes","Yes","Yes","Yes","1.00","2016-05-04","2016-05-04 06:00:29",
It is more or less impossible to migrate from another system to vgcollect as you need the vgcollect-specific ID for each game.