factmsieve.py does not wait for completion of polynomial selection by msieve

[maxal]

I'm using factmsieve.py version 0.86, which for large enough numbers (with > 98 digits) performs polynomial selection with msieve. However, there must a bug, since while it runs a given number (MS_THREADS) of msieve copies with various selection parameters in parallel, it does not wait for their completion, and just immediately exists with the error message "could not find any polynomials" (a typical screenshot is quoted below). Interestingly, it leaves the msieve copies still working in the background and doing their job.

So, my workaround is the following:
1. Run factmsieve.py as above and receive the error message "could not find any polynomials".
2. Wait until the msieve copies complete their job (in the background) and create files with polynomial candidates.
3. Delete the .lcf file
4. Start factmsieve.py again - it runs msieve copies again but also immediately finds the msieve results from the previous run available, and picks a polynomial from them.
5. Kill msieve copies running in background (since the polynomial selection was already done).
6. Let factmsieve run normally and complete the remaining steps.

It's somewhat cumbersome doing this each time.
Could someone experienced in Python and multithreading look at factmsieve.py code and make it patiently wait for msieve's copies doing polynomial selection to complete their job?
Thank you!

$ ../factmsieve.py my.n
-> ________________________________________________________________
-> | Running factmsieve.py, a Python driver for MSIEVE with GGNFS |
-> | sieving support. It is Copyright, 2010, Brian Gladman and is |
-> | a conversion of factmsieve.pl that is Copyright, 2004, Chris |
-> | Monico.   Version 0.86 (Python 2.6 or later) 20th June 2011. |
-> |______________________________________________________________|
-> Running Python 2.7
-> This is client 1 of 1
-> Running on 38 Cores with 1 hyper-thread per Core
-> Working with NAME = my
-> Found n = 750412794244466806469094249756154370232848447008544287170986475690195640863077174145983232360052408915373815673023945081543.
-> Polynomial file my.poly does not exist!
-> Running polynomial selection ...
-> ./msieve -s ../111/my.dat.T0 -l ../111/my.log.T0 -i ../111/my.ini.T0 -nf ../111/my.fb.T0 -np 1,100 -v > ../111/my.msp.T0
-> ./msieve -s ../111/my.dat.T1 -l ../111/my.log.T1 -i ../111/my.ini.T1 -nf ../111/my.fb.T1 -np 101,200 -v > ../111/my.msp.T1

...skipped...

-> ./msieve -s ../111/my.dat.T37 -l ../111/my.log.T37 -i ../111/my.ini.T37 -nf ../111/my.fb.T37 -np 4201,4300 -v >> ../111/my.msp.T37
could not find any polynomials
could not find any polynomials