First off: good choice on the bot.
2nd: Bad choice about the gap, you will die alot, cause of following reasons: bad gear, low gear, low items (NPC), bad staff, no gold
Lower your gap to 2 for now, later to 3, and after 8D go for a 4 gap, ..
About the train places .. hmm .. i would say go for the crabs at Smk Beach till you dont get anything anymore from them. Afterwards search for those brown wolves ( i think they are something about 24-25) and then for the evil order warriors (they are very slow, so if you keep your Berserk for giants, pick vigors up), after them it will get harder .. the places in front of Samarkand are hard to manage (kokurus / ongs / huns), so better look for mobs in front of DW (there are some Mag damage dealing mobs over there, also those Hyeungchones arent hard to deal with), and move afterwards to those black Scorpions ..
If you dont know what im talking about, look for a monster map, and you will find that mobs. If this is your first charakter, then play more with hands, you can still bot when you are not in front of your computer .. i hope it wasnt to confusing for you :)