If picking up a blueprint book from the library, using shift-scroll wheel to select a print, and then placing it down - the LuaRecord you get in your events is the blueprint-book you picked up out of your library. LuaRecord::get_active_index() returns the "slot" in the blueprint-book of the selected blueprint. This is similar to LuaItemCommon::active_index. However, in LuaRecord::contents[] the indices are sequential without gaps. There is no analogue to LuaItemCommon::get_inventory() to get the blueprint(-book) at the book's slot location. Thus, there is no relationship between the result of LuaRecord::get_active_index() and an actual LuaRecord in the LuaRecord::contents[] table.
Showing the selected blueprint is in "slot" 3 of the blueprint-book
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Command to get the active index returns "3", but using that index to get the actual blueprint is unsuccessful since there is no key "3" in the LuaRecord::contents[] table. The blueprint in question is actually at key "2".
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