There is no way to go back to the previous shortcut keys that was used before. There is a way to redefine the shortcuts to be used, by the functionality is mind-numbingly limited. Strangely enough the original shortcuts can not be selected by default. If it is possible, I have not found a way.

Review the following picture on how shortcut mapping can be changed via the software options.

Another way is to use a 3rd party software to do a remapping of shortcuts. I rather like the scripting based ones where you can say the script is active when TIA Portal is active and the SCROLL LOCK is active.