Never mind all i needed to do was make sure the SU_dynamiccomponets.rb file was coppied and renamed to dynamiccomponets.rb. After doing this all the plugins seem to work.

Do NOT simple copy the Plugins folder contents. 😲
There were many updates to Plugins over the last year or more to suit Ruby2 - used since v2014.
You should install all available versions of your Plugins from the PluginStore...

The SketchUcation PluginStore dialog lets you Auto-Install - you can copy a v2015 Plugins folder safely to another v2015 installation...
A very few Plugins have not been updated to suit Ruby2, so they are unlikely to work in v2015.
You can but test those that are not available in the SCF PluginStore, EWHouse etc and ask...

If in doubt contact the Plugin's author directly...
Most of the mainstream authors have updated their scripts over the last year or so...
So those should be OK.

Also, e.g. with his permission I have recently updated many of Didier Bur's scripts to suit all available SUp versions...
So those are definitely the ones to get...

Browse the PluginStore to see the updates........

EDIT:

In the example error-code you provide the error is quite clearly explained...
@dlg.add_action_callback("init"){|**@dlg**, param|......
To fix it rename it ' dlg', if it's used anywhere inside the {} [which is unlikely] then change those references to match...

I suspect that most of the other errors will be fixed by getting the proper [latest] versions of the scripts...