Yes of course.
For example you can create module - Events and use something like this
Option Explicit
Function InitAlphacamAddIn(AcamVersion As Long) As Integer
Dim fr As Frame
Set fr = App.Frame
fr.AddMenuItem2 "Test_1111", "show_Form1", acamMenuNEW, "&Write something"
InitAlphacamAddIn = 1
End Function
Function show_Form1()
Load FrmMain
FrmMain.Show
End Function
Check also API documentation in Alphacam - try find Frame.AddMenuItem2