I've owned my 06 Mazda6 2.0 Sport for 8 months and not had a problem with it.
About 20 miles into my daily 25 mile journey into work (mostly motorway) my DPF light started flashing. I noticed that I'd also lost a lot of power. I drove the last 5 miles carefully and immediately checked the manual. As advised, I called my local dealer.
The dealer didn't sound too concerned. The car is due for it's 50k service in about 2k miles and he said it just needed the service, telling me I was fine to drive it for the 2 weeks it would take to book it in.

I had a bit of a bad feeling about it so called another dealer another 10 miles away. He said it was likely to be the service but it could have been a more serious problem. Driving the car with a DPF problem could mean a bill of a few thousand pounds!
He explained a few things about the DPF, inc. the tell tale sign of the oil level being at the x point on the dip stick. I recalled that only a few weeks ago my oil light was starting to flicker when I went around a right hand corner. I thought this was unusual as I check my oil level regularly. As the special grade oil is difficult to buy from local retailers I took it to my local independent garage who topped it up for me. He put a little under 2 litres in, a surprising amount when I'd checked it about two weeks previous (it wasn't near the full mark but certainly wasn't low). After suspecting I may have an oil leak I've been religiously checking since and the level has been pretty constant.
I checked the oil after the conversation expecting it to be near the x mark. It was a possibility that my local garage had put too much oil in or that fuel was entering the sump from the issue with the DPF. It was possibly a little lower than the last level check but certainly the level wasn't anything that would ring alarm bells for me.

The car sat on my driveway for a few days and then I took it to the second dealer. Before I left there was oil on the dip stick. A little lower than the day before.
When we got to the dealer (about a 30 mile drive) there was no oil on the stick. But the oil pressure light wasn't on?!?!
After some exploratory work the dealer told me the underside was caked in oil. Due to the cover on the bottom of the car the oil hasn't leaked onto my driveway for the tell tale patch.

I understand that the oil leak is a problem but I'm not sure why there was no oil on the dipstick but the oil pressure light failed to illuminate. But when there was oil on the stick a few weeks ago the light illuminated briefly.

What does the oil level have to do with the DPF?

The dealer didn't sound too surprised when I said that the DPF light hadn't illuminated previously (or maybe he thought I was fibbing?). As I understand the DPF light illuminates when it's been unable to regenerate itself, it alerts the driver who will need to run the car at over 25mph and 2.5krpm for 10-15minutes for the DPF to regenerate.

From the posts I've read across many forums most people have had the DPF light illuminate as they only drive a few miles so often.
I drive at least 50 miles a day and I'm often cruising with high revs so why should the DPF have a problem regenerating itself?

Can anyone shed any light on this matter? I'm very confused as to what's to related to what.