DNN Scheduler won't run my custom schedule - dotnetnuke

Question

I have created a class Library and made sure it inherits
DotNetNuke.Services.Scheduling.SchedulerClient
And have then overrided the DoWork() sub.
Then in dnn host settings > scheduler added a new scheduler Item.
in the textbox marked : Full Class Name and Assembly:
Namespace.Classname, Dllname
checked the Enable Schedule box and added a run time interval of 5mins and enabled catch up.
also added the list of tables that the class uses. and keep 5 records of history
I then saved it,
In the view schedule Status I get this:
Name | Next Start | OverDue(s) | Time Remaining
Sub reminder | 11/12/2010 9:52:02 AM | 3.5 | 0
Using the scheduler in request mode.
Thanks in advance for any help.
Update :
Ok, I created a new class library project called "SubRenewal"
Renamed the vb file Test and added the below to the file
Namespce Matts
Public Class Test
Inherits Dnn.Services.Scheduling.SchedulerClient
Public overrides Sub DoWork()
Me.ScheduleHistoryItem.addLogNote("I ran")
end Sub
End Class
End Namespace
On the Scheduler Page I put :
Friendly Name Tester
Full Class name and assembly Matts.Test,SubRenwal
Enabled Yes
Time Lapse 10 s
Rety frequency -
Run on Event None
And left everything else blank and saved it. Still nothing in Scheduler or Item History. Also theres nothing in the event viewer

Answer 1

I would suggest following steps to get started with scheduler development and debugging:
Create a new class library probject and add reference of dotnetnuke and related dlls in it
add reference of the same project to your dnn project
add a new vb or c# file to implement scheduler
add code lines to create entries in schedule history and no other code
test your scheduler
register your new scheduler from dotentnuke website host account
Please note that as soon as you add a new scheduler item, it will fire the scheduler.
I hope this will help you. I will suggest to remove the entry of scheduler you already having, reset your website instance ( iis or asp.net development server) and try adding it again using the above method
Hope this will help you

Answer 2

Firstly Id Like to thank Lakhlan, for his help without him I wouldnt of spotted the mistake.
I beleive the issue was one of two things first one is that I was registering a reference to another custom module to allow me to localise some of the output text.
Also I added the new constructor below
Public Sub New(ByVal objSceduleHistoryItem As DotNetNuke.Services.Scheduling.ScheduleHistoryItem)
MyBase.New()
Me.ScheduleHistoryItem = objSceduleHistoryItem
End Sub
Thanks again would up vote you for your help but cant :(