Aging simulation fails in mode URI_mode: appendage

Dear all, 

I would like to know what is causing the issue I am getting with Reliability simulation using my own aging model.

When I specify for URI mode: "agemos", it succeeds but  I am getting infinity for lifetime and age = 0

Then , when I specify  "appendage" for URI mode, the simulation fails and I get the following error:

Error found by spectre in `inv_I0_0', during circuit read-in.
ERROR (SFE-874): "input.scs_aged" 8126: Unexpected equals "=".

as can be seen in spectre out here attached

Cadence (R) Virtuoso (R) Spectre (R) Circuit Simulator
Version 13.1.1.252.isr11 64bit -- 14 Aug 2014
Copyright (C) 1989-2014 Cadence Design Systems, Inc. All rights reserved worldwide. Cadence, Virtuoso and Spectre are registered trademarks of Cadence Design Systems, Inc. All others are the property of their respective holders.

Includes RSA BSAFE(R) Cryptographic or Security Protocol Software from RSA Security, Inc.

Memory available: 40.9866 GB physical: 101.4022 GB
CPU Type: Intel(R) Xeon(R) CPU E5-2430L 0 @ 2.00GHz
Processor PhysicalID CoreID Frequency Load
0 0 0 2000.0 0.5
1 1 0 2000.0 0.2
2 0 1 2000.0 0.2
3 1 1 2000.0 0.2
4 0 2 2000.0 0.1
5 1 2 2000.0 0.1
6 0 3 2000.0 0.1
7 1 3 2000.0 0.0
8 0 4 2000.0 0.0
9 1 4 2000.0 0.0
10 0 5 2000.0 0.1
11 1 5 2000.0 0.0
12 0 0 2000.0 0.2
13 1 0 2000.0 0.3
14 0 1 2000.0 0.1
15 1 1 2000.0 0.1
16 0 2 2000.0 0.1
17 1 2 2000.0 0.1
18 0 3 2000.0 0.1
19 1 3 2000.0 0.0
20 0 4 2000.0 0.0
21 1 4 2000.0 0.0
22 0 5 2000.0 0.0
23 1 5 2000.0 0.0

Simulating `input.scs_aged' on m-design.cdta.dz at 5:14:41 PM, Thur Feb 11, 2016 (process id: 19608).
Current working directory: /home/CDTA/achenouf/simulation/URI_test/inv_bench/adexl/results/data/Interactive.675/3/URI_test:inv_bench:4/netlist
Command line:
/opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/bin/spectre -64 \
+escchars +log ../psf/spectre.out -format psfxl -raw ../psf \
+lqtimeout 900 -maxw 5 -maxn 5 +logstatus input.scs_aged

Loading /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/cmi/lib/64bit/5.0/libinfineon_sh.so ...
Loading /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/cmi/lib/64bit/5.0/libphilips_o_sh.so ...
Loading /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/cmi/lib/64bit/5.0/libphilips_sh.so ...
Loading /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/cmi/lib/64bit/5.0/libsparam_sh.so ...
Loading /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/cmi/lib/64bit/5.0/libstmodels_sh.so ...
Reading file: /home/CDTA/achenouf/simulation/URI_test/inv_bench/adexl/results/data/Interactive.675/3/URI_test:inv_bench:4/netlist/input.scs_aged
Reading file: /opt/Cadence/14-15/MMSIM_13.11.252/tools.lnx86/spectre/etc/configs/spectre.cfg

Error found by spectre in `inv_I0_0', during circuit read-in.
ERROR (SFE-874): "input.scs_aged" 8126: Unexpected equals "=".

Time for NDB Parsing: CPU = 115.983 ms, elapsed = 160.074 ms.
Time accumulated: CPU = 139.978 ms, elapsed = 160.083 ms.
Peak resident memory used = 43 Mbytes.

Time for parsing: CPU = 0 s, elapsed = 14.0667 us.
Time accumulated: CPU = 139.978 ms, elapsed = 160.343 ms.
Peak resident memory used = 43 Mbytes.

~~~~~~~~~~~~~~~~~~~~~~
Pre-Simulation Summary
~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~

Aggregate audit (5:14:42 PM, Thur Feb 11, 2016):
Time used: CPU = 146 ms, elapsed = 166 ms, util. = 87.8%.
Time spent in licensing: elapsed = 54.8 ms, percentage of total = 32.9%.
Peak memory used = 43 Mbytes.
Simulation started at: 5:14:41 PM, Thur Feb 11, 2016, ended at: 5:14:42 PM, Thur Feb 11, 2016, with elapsed time (wall clock): 166 ms.
spectre completes with 1 error, 0 warnings, and 0 notices.
spectre terminated prematurely due to fatal error.