and with SHIFT modifier 
are the same. Most of the differences lie in the added assignments with the modifiers ALTGR 
and SHIFT + ALTGR. 
The Finnish multilingual keyboard layout extends the old Finnish layout with several additional characters from AltGr combinations. With all these additions, it should be relatively easy to enter most characters used in main European languages (excluding, e.g., Greek).
Despite Finnish Multilingual layout being standardised since 2008, it is still not present in Windows OS by default (at least not in mine Windows 7 Home Premium). Because of my relocation to Germany, a need rose for me to write German. Luckily the character set can be quite easily obtained from the basic Finnish layout. Only ü needs two key presses instead of one, but then ß is completely missing. I searched for a while how to use the extended keyboard layout in Windows, and the conclusion from the search was that is just isn't available. So I needed to do something. The something turned out to be actually quite easy: using Microsoft Keyboard Layout Creator create a proper layout and install it. Even though the process was really easy, I want to share the ready layout here, if somebody else might need it, too.
The layout is based on the traditional Finnish layout. For this reason, the key assignments without any modifier and with SHIFT modifier are the same. Most of the differences lie in the added assignments with the modifiers ALTGR and SHIFT + ALTGR.
If you want to use the Microsoft Keyboard Layout Creator 1.4 yourself and edit the layout further, here is the project file for that purpose. With that you can builf the required installation files yourself. However, here are the installation files for amd64, i386, and ia64. I do not take any responsibility for using the provided files in your system. You are doing it completely on your own risk. However, I can say that at least i386 did work on my system, and has been in use constantly after installation.
If you find mistakes here, or would like to comment otherwise, please send me an email to the address you'll find on the main page.
paulus, 2010/11/26