OK Matt, I'm back. Here we go dood..
First, make sure you have the driver installed and working. In Cubase; Devices>Device Setup...>VST Audio System. Drop down menu should have Alpha listed. Select that. Also, make the Lexicon Alpha the 'default audio device' in
Windows. Start>
Control Panel>Sounds (or whatever your OS calls it. Different for XP/Vista/W7).
Ok, open Cubase. Select 'Empty' project to start. Now, go to Devices>VST Connections. hit the 'Inputs' tab at the top left. Under that select 'Add Bus'. 'Add Input Bus' window pops up. Change the configuration to 'mono' (drop down menu designated by the down
arrow). Click on 'mono', then 'Add Bus' tab to the right. Now, make sure the input channel you are using on
the Alpha is selected there. You only have two. Channel 1 being the instrument input, and channel 2 being the mic input. You said you are using a 58, so select input #2. You change this by left clicking on the line highlighted in yellow. Select input 2. Done...
Now, close that window and back to the project window (the main Cubase screen you see when project is first opened).
Next; Project>Add Track>Audio. 'Add Audio Track' window appears. Under 'Configuration' again select 'Mono' then Add Track. Do not use a stereo track here, as it will screw you...
Now by default, your mono audio track will have your 'mono' input bus you created selected in the 'Inspector' window at the left side of the project window. We can discuss changing that later, which you will need to do if you want to record from a different input channel of the Lexicon (meaning instrument input).
Hit the record button (looks like a target and turns red). Hit the monitor button (looks like a side view of a speaker). You should hear and see the levels from your microphone through the interface coming in on meter on the right side of your track name. Hit Record on your transport and go to town.
When you are done recording, toggle the monitor button to hear back the track.
This is actually easier is you go to File>Preferences>VST>Auto Monitoring. From the drop down menu select 'Tapemachine Style'. It will automatically enable/disable the monitor button when you hit record or stop recording.
Eventually this will all make sense man. When you get into multitracking with multiple inputs, you will see just why what seems so complex now, makes so much sense to have these setup requirements. Trust me, it took me a long time to get my head around it... You are just where I was years ago.
I'm here to help man.