I-TASSER 5.1 PRTMalign error

Hello, I have installed I-TASSER 5.1 on one of our linux machines (running Ubuntu 16.04) and have tried a test run using a short sequence, as advised.

However, I am getting this error:

(...)
7 run COACH to predict function: Ligand-binding site,EC number,GO terms...
/data/2TBssd1/usr/local/i-tasser/I-TASSER5.1/I-TASSERmod/runCOACH.pl -pkgdir /data/2TBssd1/usr/local/i-tasser/I-TASSER5.1 -libdir /data/2TBssd1/usr/local/i-tasser/ITLIB -runstyle serial -protname seq.fasta -model model1.pdb -datadir /data/2TBssd1/usr/local/i-tasser/test -homoflag real -idcut 1 -LBS true -EC true -GO true
cp: cannot stat '/data/2TBssd1/usr/local/i-tasser/ITLIB/PDB//3n96A.pdb': No such file or directory
cp: cannot stat '/data/2TBssd1/usr/local/i-tasser/ITLIB/GO/MTX/3n96A.mtx': No such file or directory
cp: cannot stat '/data/2TBssd1/usr/local/i-tasser/ITLIB/GO/PRF/3n96A.prf': No such file or directory
At line 174 of file PRTMalign.f
Fortran runtime error: No such file or directory
Argument "74A" isn't numeric in sprintf at /data/2TBssd1/usr/local/i-tasser/test/model1/cofactor/CF_seq.fasta_model1.pl line 2230, line 221.
Argument "74A" isn't numeric in sprintf at /data/2TBssd1/usr/local/i-tasser/test/model1/cofactor/CF_seq.fasta_model1.pl line 2230, line 222.
cp: cannot stat '/data/2TBssd1/usr/local/i-tasser/test/model1/tmsite/tms_*.pdb': No such file or directory
cat: tms_1uzjA_BS01_CA.pdb: No such file or directory
cat: tms_5ky8B_BS01_BGC.pdb: No such file or directory
cat: tms_5vygB_BS01_GXX.pdb: No such file or directory

...and indeed, the 3n96A.* files mentioned above appear to be missing from the libraries, which I just downloaded yesterday.

How to fix this problem?

Thanks and best regards,

Luca