Trouble with custom namespace flex 2 (Could not resolve component implementation)

[jwriteclub]

I feel like this must be addressed somewhere, but I cannot seem to find a good explanation, so a link somewhere (or an explanation) would be much appreciated.

Using Adobe Flex Builder 2.0.1.

I created a custom component based on Canvas. Added a few items and a little script logic.

I saved the component in projectFolder/data_access/DataSelector.mxml and its actionscript in projectFolder/data_access/DataSelector.as.

When I returned to the main application "DataSelector" was listed as a custom component. I dragged one onto the stage, where it showed up.

However, when a try to compile, I keep getting the error: "Could not resolve <ns1:DataSelector> to a component implementation.".

Looking at the code of the main file I see:

<mx:Application xmlns:ns1="*" xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" initialize="onInit();">
. . .
<ns1:DataSelector x="48" y="10">
</ns1:DataSelector>

My question is two fold:

1) How do I make this compile (any method)
2) How do I assign a custom namespace to my component (i.e. com.mydomain.*) if this is possible.

~ Christopher

Edit: I should probably note that I have tried changing the ns1 line to xmlns:ns1="data_access.*", xmlns:ns1="data_access.DataSelector", and xmlns:ns1="cal_reader.data_access.*" (where cal_reader is the name of both my application and the folder it is in.