Teranex AV - conversion NTSC-PAL defects

Using a Teranex AV device for a conversion from NTSC into PAL. The problem is that the resulting video has a so called "ghost-effect" when there is panning of quick movement on video (jitter and doubling of the image on the screen). Specially seen on pauses.
Or another fault - some freeze frames appear (say, each 5th frame)
Any advice regarding this? Thank you in advance.
OS: Windows 7.

This is about all what Teranex can do in case of fps conversion. It only supports very simple methods.
If you want to do proper conversion you need to use Alchemist or Tachyon.

Thank you. Could a Davinci Resolve Studio software help in this matter?

Not sure how well Resolve will handle interlaced footage. In such a case proper approach is to deinterlace source to double fps, do conversion and interlace back to final 50i video. I don't think Resolve can do this well.
You will get better result with this:
https://forum.doom9.org/showthread.php?t=174793
but you need to know avisynth a bit. I can convert it for you (if you have fast internet), but I would want small fee.