Hesskaz, I went through a very similar situation in 2007 where I moved to a new company and despite giving me assurance about my new work permit, they didn't apply for it. I started working for them and for some reasons it took around 4 months to get my work permit.
After getting the work permit, I sent my passport for the FLR stamping and it got refused. The reason was "breaching of immigration law". Since I started working for the company without receiving a valid WP, my FLR got refused. I mentioned to the home office about the situation where I was forcing my employer to get the work permit and it was on delay from their side but no result. According to home office employer and employee are equally responsibile for making sure that the immigration law is followed. Not knowing a law is not an excuse. So I decided to leave the country. I went back to my home country and with the help of another employer I got a new Work Permit and I came back to UK.
Regarding your questions
1) I believe your immigration history isn't that bad since you left the country at your own expenses and with in the date mentioned but I think since it was a breach of immigration law, you may not be able to enter the country for a year (
http://www.ukba.homeoffice.gov.uk/polic ... les/part9/). The experts here would be able to advice you more on this.
2) If you want to work in UK I think Tier 2 is the option.
I hope this helps.
Regards,