I have tried the following:

For Field 1 - SUBSTRING([RefNumber],1,1)

This correctly returns the first digit.

For Field 3 - SUBSTRING([RefNumber],FINDSTRING("/",[RefNumber],3),(FINDSTRING("$",[RefNumber],3)) - FINDSTRING("/",[RefNumber],3))

This is accepted by the Derived COlumn transformation, but when I debug the package it fails with the following:

[Derived Column [4862]] Error: SSIS Error Code DTS_E_INDUCEDTRANSFORMFAILUREONERROR. The "component "Derived Column" (4862)" failed because error code 0xC0049067 occurred, and the error row disposition on "output column "Derived Column 1" (10186)" specifies failure on error. An error occurred on the specified object of the specified component. There may be error messages posted before this with more information about the failure.

[Derived Column [4862]] Error: An error occurred while evaluating the function.

Can anyone help me please?

Paul