By "main welcome page", do you mean the TWC MainMenu tiddler? If so, then that tiddler should have been imported with the rest.
And, if you used simple bracketed link syntax in TWC, that syntax is the same in TW5, so all the links to your topics and sub-topics should still be valid.
The only thing is that there is no MainMenu *display* in the default TW5 layout (just the StoryRiver and SideBar), so it doesn't appear automatically.
The default sidebar tabs only include "open, recent, tools, more". The Contents tab you see in the Sidebar on TiddlyWiki.com is an extra customization so it can show the TW documentation that is included on the site.
The TW5 "empty.html" does *not* have that customization, so you need to add it.
Fortunately, it's incredibly simple:
To add your MainMenu tiddler to the Sidebar tabs, just tag it with "$:/tags/sidebar". If you want the tab to read "Contents", add a *field* named "caption" to the MainMenu tiddler, and set the value of that field to the desired tab text.
That should do it.
Let me know how you get on...
enjoy,
-e
Eric Shulman
TiddlyTools / ELS Design Studios
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