Make sure all the XML files are saved as Unicode. I assume 7zip would create a proper zip archive. You can also try using the built in Zip Wizard in Windows.
Here is an example of a ScriptInfo.xml file
XML code:
<?xml version="1.0" encoding="UTF-16"?>
<ScriptInfo xmlns="urn:msgplus:scripts" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:msgplus:scripts PlusScripts.xsd">
<Information>
<Name>Screenshot Sender</Name>
<Description>Allows you to easily send screenshots to your contacts.</Description>
<Author>matty, Mattias & Dempsey</Author>
<AboutUrl>http://beta.screenshotsender.com</AboutUrl>
<Version>5</Version>
<UpdateId>SS5</UpdateId>
<Build>0062</Build>
</Information>
</ScriptInfo>
Also make sure that the files are in the root of the Zip archive not in a sub folder.
You can also post the PLSC here and we can have a look at it.
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