I am not clear what you are calling alternate depreciation book parts.
If you mean the field Alternate Depreciation: this is saying that a proposal should calculate using the primary depreciation method until the depreciation amount result is less than what the Alternate method would generate, at which time the calculation switches from the primary method to the Alternate method.
If you mean having additional books beside the straight-line for an asset, then your dep'n proposal should generate records for those amounts (usually posted to a different posting layer like TAX or OPERATING).
Hopefully that helps?
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