TSIS Next.  The TSIS 6.1 installation now automatically installs the TSIS Next interface program alongside the original TSIS interface program.   Users can choose between launching the original TSIS (TShell) or the new TSIS Next, depending on their needs and preferences.

Modeling Options.  1) CORSIM can now simulate up to nine lanes per intersection approach.  2) Emergency vehicles can now be simulated, and can cause signal pre-emption if desired.  3) CORSIM and TRAFVU can now handle left-hand drive networks, with TSIS Next as the preferred input editor.

Simulation Logic.  In addition to containing all of the improvements from build 507, build 508 now offers improved simulation logic for spillback checking with diagonal movements, triple turn pocket lanes, discretionary lane changes, buses moving between NETSIM and FRESIM, and setting goal lanes.

Documentation Fixes, Bug Fixes, and Miscellaneous Changes.  Information in the HTML Help files was corrected and improved.  New documentation for path following and emergency vehicles was added.  Certain inputs that could cause crashes in CORSIM before will now cause standard error messages and/or no errors.  A confusing TShell warning message for "restricted" Windows users has been eliminated.  TRAFED no longer exports record type 49 (actuated timing transition) for single-period files.  Brand-new sample networks are now installed on the users computer for demonstrating various CORSIM features.  Checkboxes in the output processor, which would cause incorrect results if they were all turned on at once, have been corrected.  Improvements and corrections have been made to TSIS Next, which was originally available as a free download.  The TSIS 6.1 installation CD contains an updated sample runtime extension (RTE), an updated RTE Developers Guide, and an updated CORSIM Data Dictionary.