Unable to run DVB-S2 tx examples on GNU Radio Companion 3.8.1.0(Window 10,64bit)

Hello 

I am experimenting with DVB-S2.  The particular example is :

https://github.com/gnuradio/gnuradio/blob/v3.8.1.0/gr-dtv/examples/dvbs2_tx.grc

In the past, I have used GNU Radio Companion 3.7.13.5 (windows version, WIN 10 , 64 bit) and corresponding dvbs2_tx.grc (revision tag 3.7.13.5), everything was fine.

Now I installed GNU Radio 3.8.1.0 and try to run updated dvbs2_tx.grc (revision tag 3.8.1.0) , i encounted numerous Can not cast evaluated value 'all' to type <type 'str'>

error messages.

I did try to see the search for similar problems and recommendations before posting.

Any help!!!

Regards 

Priyasloka