hey scotsman
best info is in the mach3 manual needs to be printed you can copy it or buy a printed manual .and there are video's also wiki (cnc zone u can copy the glossary)
this what i was told when i first came in here (mach3 is not a plug in play) it was very blunt and (you have allot of reading) and that is no lie its allot of reading
i would start at software installation and configuration ground up.
It is not a good idea to plug or unplug parallel cable while PC is on.
wiki has allot of info too its like ping pong you read out of the manual, you read wiki, you watch the video, all of the examples hopefully start to fit together. then when you do get a answer 90% of the time you are refer ed to a video or a chapter in the manual. there is not short cuts even if you bought files unless they where custom made for your cnc and milling stock you are still going to have know everything .
do your best( everything has a name) helps if we know what you are talking about
You might want to set to metric i set all my software to standard im thinking now wrong choice on cam /bam software
good luck
mikee