Use diskpart to change partitions letters in MDT

In Run command line task put:
cmd.exe /c diskpart /s "%scriptroot%\changepart.txt"

Then in \Deploymentshare\Scripts folder create changepart.txt file and type into it something like:

select disk 1
online disk noerr
attributes disk clear readonly noerr
select volume 0
assign letter=F noerr
select volume 2
assign letter=D noerr
exit

MDT asking for product key during deployment

If You are using Windows installation files from OEM dvd MDT will ask You for product key during deployment even if You specify SkipProductKey=YES

To prevent it copy product key from product.ini file from dvd sources catalog and put it in unattend.xml for specific task sequence

MDT format just first partition

If You want format only first partition during deployment task sequence just disable Format and Partition task. The setup will carry out formatting first partition