This is what I found poking around on the web:
Strangely enough I had exactly the same problem but today managed to fit the new inner glass and door panels without any problems, here is how.
YOU NEED 2 PEOPLE FOR THIS STEP. Open the door, at the top are 2 large plastics flat head screws, undo these making sure your helper is holding the door securely or itll fall on the floor, te door will unhook once the screws are fully undone
Once off you can close the microwave back up.
Now there are two screws, one in each top corner holding a funny looking plastic wing shape that slides into the inner door. They have a star screw head. Undo both of these and remove the plastic wings. When you remove these the panel underneath will try to fall off so be prepared to catch it, along with the plastic screws undone in step 1. This now unhooks like the main door did.
From here you'll be able to see the back of the inner glass. This is held in by a mesh at the back and about 15 screws, star headed again. you can simply remove all of these, that will release the front panel over the inner glass, again, you might want someone to hold the door open so the panel does not drop when you remove the last screws.
Thats it as far as taking the microwave apart. put your new glass in, remembering to make sure the rubber seal is put back between the glass and inner door.
Simply reverse the process.
It took me approximately 1 hour and I am by no means a DIY person.
Good Luck
Mike
By Jenny - Ealing - Fix-It Beginner
This inner glass door panel fitted my Bosch combination Microwave/oven perfectly.I had to take out 32 screws to remove the shattered glass. Replacing the glass was a bit fiddly as I had to use tape on all four corners to line up the glass panel with the gasket and mesh (a previous reviewer mentioned this in his review). I was then able to replace the 32 screws. The time I took to replace the glass was worthwhile, I now have a working combination oven.I wouldn't have been able to do it without reading previous reviews, thank you to all who took the trouble to write these reviews.
This glass panel fitted my Neff combination Microwave/ oven perfectly (inner glass door). Fitting it involves working from the outside in , removing the outer and middle glass doors then replacing the shattered inner glass door . This involved removing over 32 screws designed to clamp the door evely in place. To line up the glass panel with the gasket and mesh it needs to be held horizontally with the glass temporarily held in place with tape. Fiddly but straightforward.
http://www.howtomendit.com/answers.php?id=188594
Robert, January 2012
