I made my project completely on blueprint, but for adding certain plugin i added a c++ class, now my project files gives error that project could not be compiled try rebuilding from the source

i wanted to add kinect4u in my project file, but it told me to create a c++ class first.
After adding a c++ class my project file fails to open. please help

From K4U’s website:

HOW CAN I PACKAGE MY PROJECT?

While we are constantly searching for
alternatives, in Unreal there is
currently no way to package a project
that includes a plugin without source
code. This is a problem that Epic is
also actively working on and is slated
to be fixed in 2015. However,
depending on your needs, it may not be
necessary to package your plugin for
deployment. This is particularly
relevant to installations and
exhibits, running your project from
inside the editor as a new editor
window or a standalone game, these
both allow you resolution and full
screen control equivalent to that of a
packaged project.

If you absolutely need to package the
project right now, there are two
options:

Acquire a source code license from us.
The cost varies depending on the scale
of your project, so please contact us
for more detail. For a fee, we can
package your application for you. The
cost varies depending on how much
effort it requires, but generally
ranges between $200 - $400 USD for
projects that can be packaged directly
from engine. For projects that require
compilation from source, we recommend
that you contact us to acquire a
source license.

They’re not clear if you simply need your project in c++; or if you need the Engine Source c++.
I’m assuming that the plugin must be added in to the Engine’s Source folder.
If that’s the case, you’ll need to get the engine source code from GitHub; integrate the K4U plugin and compile.

I know the post says 2015; but it’s looking like it hasn’t been fixed yet.

ok, let me be clearer the problem is I added the plugin just to test and explore but now I don’t want to use it. My project was completely built on blueprints and now I can’t open because of the above said problem