I have listened to the first download, and your pronunciation is very good - I could understand every word. Understand though, that to a native English speaker, most people who learn English as a second language do have a strong accent: we can tell if a person was born in India, or Japan, or China - or America! But then, to my friends in the United States I have an accent - a pronounced British accent!
There are a couple of words I think I can help you with:
were an English group
You are pronouncing the -re too strongly, so that it sounds like were-ra. "were" rhymes with her, fur, sir. Don't let the -e on the end of "were" fool you into thinking it has to be pronounced. Think of it as spelt "wer"
musicians: you seem to be saying, music -sons. Music is pronounced as if it were spelt musik (as you pronounce it when saying 'musicians - musik-sons"
Try saying it as if it were spelt mu-SISH-uns. But again, watch the 'mu' sound - it is pronounced as if you are saying 'myu', rather than 'moo'
commercially : you seem to be saying it like, COM -ersly. Breaking the sounds up, it would be : com - MEERSH-ally - the 'i' sound is what we call "swallowed', so that it is barely pronounced.
I will try to listen to the other downloads in the next few days, and help some more.
Do you have an English speaker that you learn from? If so, I would think they are are American or Dutch by birth!