MAYBE
Errors:

Unhandled Exception:
System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
  at Microsoft.FSharp.Collections.MapTreeModule.find[TValue,a] (System.Collections.Generic.IComparer`1[T] comparer, TValue k, Microsoft.FSharp.Collections.MapTree`2[TKey,TValue] m) [0x0003e] in <5914a175dff9fae1a745038375a11459>:0 
  at Microsoft.FSharp.Collections.FSharpMap`2[TKey,TValue].get_Item (TKey key) [0x00001] in <5914a175dff9fae1a745038375a11459>:0 
  at Microsoft.Research.T2.Instrumentation.unrolling_trans (System.Int32 cp, System.Collections.Generic.Dictionary`2[TKey,TValue] cp_rf_lex, Microsoft.Research.T2.Programs+Program p, System.Boolean termination_only) [0x0004d] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Instrumentation.do_unrolling (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Instrumentation+LexicographicInfo lex_info, System.Int32 failure_cp, System.Collections.Generic.Dictionary`2[TKey,TValue] cp_rf_lex, Microsoft.Research.T2.Programs+Program p_final, Microsoft.Research.T2.SafetyInterface+SafetyProver safety, System.Boolean termination_only) [0x00050] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.prover[a] (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p_orig, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, Microsoft.Research.T2.Utils+SetDictionary`2[Key,Value] precondMap, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint, System.Boolean existential, System.Boolean findPreconds, System.Boolean next) [0x0073e] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.bottomUp[a] (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, System.Int32 nest_level, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint, Microsoft.Research.T2.Utils+SetDictionary`2[Key,Value] propertyMap) [0x0029e] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.bottomUpProver (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint) [0x00116] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Main.main$cont@113-1 (Microsoft.Research.T2.Arguments+runMode runMode, Microsoft.Research.T2.Parameters+parameters parameters, System.String fairness_constraint_string, Microsoft.Research.T2.Programs+Program p, Microsoft.FSharp.Core.Unit unitVar) [0x00071] in <597f4945c11a1123a745038345497f59>:0 
  at Microsoft.Research.T2.Main.main (System.String[] arguments) [0x00261] in <597f4945c11a1123a745038345497f59>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
  at Microsoft.FSharp.Collections.MapTreeModule.find[TValue,a] (System.Collections.Generic.IComparer`1[T] comparer, TValue k, Microsoft.FSharp.Collections.MapTree`2[TKey,TValue] m) [0x0003e] in <5914a175dff9fae1a745038375a11459>:0 
  at Microsoft.FSharp.Collections.FSharpMap`2[TKey,TValue].get_Item (TKey key) [0x00001] in <5914a175dff9fae1a745038375a11459>:0 
  at Microsoft.Research.T2.Instrumentation.unrolling_trans (System.Int32 cp, System.Collections.Generic.Dictionary`2[TKey,TValue] cp_rf_lex, Microsoft.Research.T2.Programs+Program p, System.Boolean termination_only) [0x0004d] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Instrumentation.do_unrolling (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Instrumentation+LexicographicInfo lex_info, System.Int32 failure_cp, System.Collections.Generic.Dictionary`2[TKey,TValue] cp_rf_lex, Microsoft.Research.T2.Programs+Program p_final, Microsoft.Research.T2.SafetyInterface+SafetyProver safety, System.Boolean termination_only) [0x00050] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.prover[a] (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p_orig, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, Microsoft.Research.T2.Utils+SetDictionary`2[Key,Value] precondMap, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint, System.Boolean existential, System.Boolean findPreconds, System.Boolean next) [0x0073e] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.bottomUp[a] (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, System.Int32 nest_level, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint, Microsoft.Research.T2.Utils+SetDictionary`2[Key,Value] propertyMap) [0x0029e] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Termination.bottomUpProver (Microsoft.Research.T2.Parameters+parameters pars, Microsoft.Research.T2.Programs+Program p, Microsoft.Research.T2.CTL+CTL_Formula f, System.Boolean termination_only, Microsoft.FSharp.Core.FSharpOption`1[T] fairness_constraint) [0x00116] in <597f493e96b5f0a0a74503833e497f59>:0 
  at Microsoft.Research.T2.Main.main$cont@113-1 (Microsoft.Research.T2.Arguments+runMode runMode, Microsoft.Research.T2.Parameters+parameters parameters, System.String fairness_constraint_string, Microsoft.Research.T2.Programs+Program p, Microsoft.FSharp.Core.Unit unitVar) [0x00071] in <597f4945c11a1123a745038345497f59>:0 
  at Microsoft.Research.T2.Main.main (System.String[] arguments) [0x00261] in <597f4945c11a1123a745038345497f59>:0