The phrase “Not a valid widget” is one of the top searched for terms here on my site, so here is a little post and explanation as to why you might be getting this error message.
First of all Adobe Captivate Widgets uses a code framework that is provided and defined by Adobe. All Adobe Captivate Widgets must adhere to some minium requirements in order to be a real Adobe Captivate Widget. When you insert a Widget in Adobe Captivate, then Adobe Captivate will check to see if it recognises the structure and coding of the file you insert as a Widget.
In case that Adobe Captivate cannot recognise the file as a Widget you will get the “Not a valid widget” error message. It doesn’t really provide you with any other information to help you troubleshoot the problem so you are on your own.
In my experience these are the most common problems when it comes to the “Not a valid widget” error message.
1. The file you have inserted is in reality not an Adobe Captivate Widget at all, but instead a regular Flash Animation / Flash SWF. Try inserting the file as an animation instead of a widget.
2. You are inserting an Adobe Captivate Widget programmed with AS2 into Adobe Captivate 5 or Adobe Captivate 5.5. These versions of Adobe Captivate only supports the AS3 programming language.
3. The file is an actual widget but it doesn’t work. There are two paths here. Either you purchased the widget from another widget developer or you tried to create your own widget.
If you purchased the widget then you should contact the developer. If you tried to program the widget yourself then you will need to go through your code and see if you have any errors or something is missing.
When it comes to developing widgets on your own you have two choices. Either you are using the standard Adobe Captivate Widget Framework (used in all the stock widgets) or you are using one of the API’s that helps you build widgets. I would definitely recommend that you use an API instead of Adobes default framework as it makes it much easier. You have a choice between using the CPGears or Widget Factory API. Both API’s will make it easier to build widgets and reduce the chance you getting a “Not a valid widget” error message since the API’s are much more logical to work with than the standard Adobe framework.