I had these issues too. I am using windows vista and DW CS4. How I solved it was I went to "my Computer" located "My Documents" and located my site folder eg "mypowerstore". I right clicked on my site folder and clicked on "properties". I then UNCHECKED the "read only" checkbox. Windows or Mac will prompt you if you want to remove "read only" from all other sub-folders, click the yes button. When you go into dreamweaver and refresh, all your files should be unlocked.
The second issue arises because powerstore is using php includes for the menu text and some images. Thats why you can see all the php icons on tyhe page, it is not an error. If you are using cs3 or cs4 you can click on the live code button to view your complete page in dreamweaver.