I've been trying to use FormInjector to create a dynamic form and not getting very far. To demonstrate this problem I've taken the FormInjectorDemo integration test and simply taken it out of the border element. It works fine until I add a t:label component in the block. It seems to me that as soon as there is more than one kind of component in the injected block, the inserted HTML is just "<li class="t-beaneditor-row"/>" without any form elements. Two textfields work, and a textfield and an 'any' component work, but not label or radio with a textfield. I suspect it's all form components.
I'll attach the modified demo. Remove the label component to see it working. (Just remove the "t:" before the label) Add back in to see it broken again.