Here's a quick way to achieve the results you want:
1) Create a tiddler called [[SetSiteSubtitle]] with the following HTML content:
------------------------------
<html><input type="button" value="$1" title="$2" style="cursor:pointer" onclick="
store.setValue('SiteSubtitle','text','<<tiddler SiteSubtitle$1>>');
"></html>
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2) Create [[SiteSubtitleEN]] containing:
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This is in English <<tiddler SetSiteSubtitle with: "PT" "Change to Portuguese">>
------------------------------
3) Create [[SiteSubtitlePT]] containing:
------------------------------
Isto é em Português <<tiddler SetSiteSubtitle with: "EN" "Mudar para Inglês">>
------------------------------
4) Set the content of [[SiteSubtitle]] to transclude the desired default, like this:
<<tiddler SiteSubtitleEN>>
That's it. You should now be able to toggle between the two alternative SiteSubtitleEN and SiteSubtitlePT definitions with a single click!
enjoy,
-e
Eric Shulman
TiddlyTools / ELS Design Studios
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