Yep, when I connected the MTH serial to the same USB<->Serial connector I use for the Legacy, it didn't like it for some reason. So, I connected the USB, that worked fine. I'm glad MTH added the USB too! 
Can 1.4 be installed & then go back to 1.3 if you have problems?
Thank you in advance
Ken
As long as you do not have the newer released Cab2. The 1.4 has code for a new display they are using in the newer systems that 1.3 does not.
The older systems can go back and forth all you want. I have been.
Thank You Marty
Two questions about Legacy v1.4:
1) What improvements and new features does it provide?
2) When you do the update, does it wipe out everything you've programmed, i.e., engines, lash-ups, routes, accessories, etc.?
Cheers!
Keith
ZW-L Control and supposedly REL 100 control for ERR products.
And no it should not.
Lionel should consider selling the upgrades for those of us with MACs and those who are not as computer savvy as some of the posters here. There can also be some resentment toward a company that is happy to sell you thousands of dollars in engines and equipment, then they have upgrades to that equipment offered as a do it yourself project, that in my case , I cannot do myself because I have a MAC. The 1.4 upgrade has little or no value to me, and likely none to many others. When the next upgrade of substance is available I would be surprised not to find it for sale loaded on a module from Lionel. Fred
People with MACs have upgraded just fine. That being said they should sell the upgrade for $50. The price of 2 black modules and $10 for making system modules.
Of course this could get costly every time an upgrade is available.
Audi, Jon posted in another thread they did try to make a Mac version but could not get it to work.
I run all Macs and am able to use LSU via Parallels
I run all Macs and am able to use LSU via Parallels
Ditto.
I apologise if I missed this but where do I find on Lionel website a manual for v1.4 or does it vary from 1.3?
Not sure if it's on the website but it is part of the download. Nothing significant. ZW-L support and REL 100. The REL 100 has an issue though. Will not support cruise M I believ. Somewhere Jon Z made a post on this after gunnrunner found it.
OK what is REL100? And what is cruise M?
Cruise M is the after market Electric RR product that upgrades TMCC1 to include speed control. It is capable of 100 speed steps. Relative 100 makes Legacy work much better with it.
Yep, the ERR Cruise Control M doesn't work at all with the Legacy R100 mode. I had an issue with it for the plain ERR Cruise Commander, I forget exactly what that was now. I'll have to test that again.
Hopefully, as Jon stated, it'll all be fixed for 1.5 this fall. 
I got my Legacy in March and it came with V1.4 from the factory. But however Lionel mailed me the V1.3 anyway.
I have Legacy and bricks 180 transformer. Is their any features or benefits for me to go to the 1.4 modules since I do not own a ZW-L?
Currently, I do not see a reason to upgrade.
David
Not really, there is a R100 feature for ERR engines if you have ghem, but nothing else you really need. You may want to do it so you have a reason to get a Black module or two and play with the LSU utility and be ready for future releases of the Legacy software
