Overbyte ICS MimeDecode issue with Embarcadero XE10.3 c++

[GE1956 0]

I have a problem using the new v8 version of OverbyteICS with MimeDecode in my C++ project with Embarcadero XE10.3. In my old studio I was able to work with v5 using the TMimeDecode component after including MimeDec.hpp in the unit header file.

In the unit cpp file I used #pragma link "MimeDec" to load the library., but in V8 I am not able to find the cpp header file in the extracted Source folder, only  the delphi version (OverbyteIcsMimeDec.pas).
Is it still possible to use the old methods connected to MimeDecode v5 (Method 'DecodeFile', field 'CurrentData', etc.) in the new Embarcadero XE10.3 (with OverbyteIcs v8)? Or is it maybe possible to use v5 with XE10.3?
Whenever I click on the unit file in the project tree, I get a message signaling that the TMimeDecode component couldn't be found. I even tried to add the OverbyteIcsMimeDec.pas file as well as further needed *.pas files,
but still the same error is shown. Is there anything else I need to do? The delphi compiler did generate the appropriate *.hpp files in my Embarcadero directory, which I did include in my project.
I did also add include "OverbyteIcsMimeDec" to my unit header file, but without success.

I would really apprecaite some help regarding my efforts to implement MimeDecodc during the migration process.