p_storageValue is the constant form parameter, while ts_storageValue is the corresponding timeseries. ts_storageValue_ is also added to handle time step aggregation and data circulation of ts_storageValue in the objective function. A new flag in p_gn called storageValueUseTimeSeries controls whether the constant p_storageValue or the timeseries ts_storageValue is used.
WIP: I have no clue what the file 1e_scenChanges.gms is supposed to do, so no changes have been made there. However, since the input data is affected by these changes, I assume that this file will need to be changed as well for this fix to work properly.