When I try to open the fonts (din 1451e,m,s) in PSPX I get a message; "The specified file cannot be identified as a supprted type." Before I unzip them I unblock them.
You cannot open TTF files with Paintshop Pro or Photoshop.
They are files you should install in Windows. After that they become available to all programs that support fonts. Note that you have to makes sure that programs like PSP should not be open while installing fonts, since many programs read fonts into their memory when they start.