"COAWST v3.7: Negative unit number error in SWAN grid (swanout2.f90)"

[build_coawst.log](https://github.com/user-attachments/files/18539983/build_coawst.log)
I was trying to run a simulator on coawst 3.7 and I got this error

Swan grid runs
....
This runs...

At line 710 of file swanout2.f90 Fortran runtime error: Unit number is negative and unit was not already opened with OPEN(NEWUNIT=...)

when I run on v3.8 I think the configuration was not compatible soo I go this error
Input Climatology File 01: in/prtbcn/[clm_prt.nc](http://clm_prt.nc/)
ROMS I/O variables Metadata File: varinfo.dat
SET_CONTACT - Illegal input file type, io_type = 0
Check KeyWord 'INP_LIB' in '[roms.in](http://roms.in/)'.
Found Error: 02 Line: 73 Source: ROMS/Utility/set_contact.F
Found Error: 02 Line: 258 Source: ROMS/Utility/inp_par.F
Found Error: 02 Line: 134 Source: ROMS/Drivers/nl_roms.h, ROMS_initialize

Elapsed wall CPU time for each process (seconds):

so for now am using v3.7 and I have attached the log above for the details of the error

Start with the attached build_coawst.log and swanout2.f90 around line 710, then compare the v3.7 SWAN-grid run with the reported v3.8 configuration errors. Reproduce the negative-unit-number failure and trace the related input configuration; done means the simulator runs without the reported Fortran runtime error and the compatible configuration is identified.

Written by the indexing model from the issue text.