Added in the API Doc file, and adjusted the created items' names.

Added the ":" to the front of the item creation so that it can be called from an external mod.
Put in an optional inventory and wield image parameter to add in colorized inventory / wield images.

mods/ITEMS/mcl_itemframes/init.lua

@@ -12,13 +12,13 @@ mcl_itemframes.create_base_definitions()
 -- necessary to maintain compatibility amongst older versions.
 mcl_itemframes.backwards_compatibility()
 
--- test for the create custom frame
+-- Define the standard frames.
 mcl_itemframes.create_custom_frame("false", "item_frame", false,
 		"mcl_itemframes_item_frame.png", mcl_colors.WHITE, "Item Frame",
-		"Can hold an item.")
+		"Can hold an item.","")
 mcl_itemframes.create_custom_frame("false", "glow_item_frame", true,
 		"mcl_itemframes_glow_item_frame.png", mcl_colors.WHITE, "Glowing Item Frame",
-		"Can hold an item and glows.")
+		"Can hold an item and glows.","")
 
 -- Register the base frame's recipes.
 -- was going to make it a specialized function, but minetest refuses to play nice.

mods/ITEMS/mcl_itemframes/item_frames_API.lua

@@ -445,8 +445,8 @@ function mcl_itemframes.create_custom_items(name, has_glow)
 			minetest.log("action", "[mcl_itemframes] create_custom_item_entity: name: " .. name .. "_map\n")
 		end
 	end
-	minetest.register_entity(name .. "_item", custom_frame_item)
+	minetest.register_entity(":" .. name .. "_item", custom_frame_item)
-	minetest.register_entity(name .. "_map", custom_frame_map_item)
+	minetest.register_entity(":" .. name .. "_map", custom_frame_map_item)
 end
 
 function mcl_itemframes.update_frame_registry(modname, name, has_glow)
@@ -470,8 +470,8 @@ function mcl_itemframes.update_frame_registry(modname, name, has_glow)
 end
 
 --- name: The name used to distinguish the item frame. Prepends "mcl_itemframes:" to the name. Example usage:
---- "glow_item_frame" creates a node named "mcl_itemframes:glow_item_frame".
+--- "glow_item_frame" creates a node named ":mcl_itemframes:glow_item_frame".
-function mcl_itemframes.create_custom_frame(modname, name, has_glow, tiles, color, ttframe, description)
+function mcl_itemframes.create_custom_frame(modname, name, has_glow, tiles, color, ttframe, description, inv_wield_image)
 	local mod_name_pass = false
 	if modname ~= "" and modname ~= "false" then
 		if minetest.get_modpath(modname) then
@@ -517,11 +517,16 @@ function mcl_itemframes.create_custom_frame(modname, name, has_glow, tiles, colo
 		custom_itemframe_definition = table.copy(mcl_itemframes.glow_frame_base)
 	end
 
+	if inv_wield_image ~= nil and inv_wield_image ~= "" then
+		custom_itemframe_definition.glow_frame_base.inventory_image = { "(" .. inv_wield_image .. "^[multiply:" .. color .. ")" }
+		custom_itemframe_definition.glow_frame_base.wield_image = { "(" .. inv_wield_image .. "^[multiply:" .. color .. ")" }
+	end
+
 	custom_itemframe_definition.tiles = { "(" .. tiles .. "^[multiply:" .. color .. ")" }
 	custom_itemframe_definition._tt_help = ttframe
 	custom_itemframe_definition.description = description
 
-	minetest.register_node(working_name, custom_itemframe_definition)
+	minetest.register_node(":" .. working_name, custom_itemframe_definition)
 
 	mcl_itemframes.update_frame_registry(modname, working_name, has_glow)
 	mcl_itemframes.custom_register_lbm(working_name)
@@ -802,7 +807,7 @@ function mcl_itemframes.backwards_compatibility ()
 	})
 	minetest.register_alias("itemframes:frame", "mcl_itemframes:item_frame")
 
-	-- To be installed when complete; adds backwards compatibility
+	-- adds backwards compatibility
 	minetest.register_alias("mcl_itemframes:item", "mcl_itemframes:item_frame_item")
 	minetest.register_alias("mcl_itemframes:map", "mcl_itemframes:item_frame_map")
 	minetest.register_alias("mcl_itemframes:glow_item", "mcl_itemframes:glow_item_frame_item")

mods/ITEMS/mcl_itemframes/item_frames_api_doc.txt

@@ -0,0 +1,36 @@
+The item frames use case is a very specific one, but... in the event that there is need for a new item frame then that
+is where this api will shine.
+
+As long as the api has been initialized (which it does in its own init.lua) then you really only need to call one
+function. That function being mcl_itemframes.create_custom_frame(modname, name, has_glow, tiles, color, ttframe,
+description, inv_wield_image). Note: unlike the Signs API, this API does not automatically create the recipe for you.
+
+Here's an explanation of create_custom_frame and an example of using it.
+
+This function is responsible for creating each frame, and handling the creation of its underlying entities.
+
+Parameters:
+* modname: Used to make sure that a specific module is installed before running the code contained within. Set to "" or
+    false, if there's not a mod to check for.
+* name: The name used to distinguish the item frame. Prepends "mcl_itemframes:" to the name. Example usage:
+    "glow_item_frame" creates a node named "mcl_itemframes:glow_item_frame".
+* has_glow: Does the frame cause the item within to glow? true / false.
+* tiles: The image files used for the item frame's object texturing.
+* color: Colorizes the frame / wield / inventory image to a specific color. Use White (#FFFFFF) to ignore.
+* ttframe: The tooltip to show for the frame.
+* description: The frame's description.
+* inv_wield_image: Optionally the image to use as the inventory and the wield image. Colorized. set to "" or nil to use
+    the default frame / glow frame images. Note: must be set if you want the inventory / wield image to be colored.
+
+example:
+-- Register the Glow Frame
+mcl_itemframes.create_custom_frame("false", "glow_item_frame", true,
+		"mcl_itemframes_glow_item_frame.png", mcl_colors.WHITE, "Glowing Item Frame",
+		"Can hold an item and glows.","")
+
+-- Register the Glow Frame's recipe
+minetest.register_craft({
+	type = "shapeless",
+	output = 'mcl_itemframes:glow_item_frame',
+	recipe = { 'mcl_mobitems:glow_ink_sac', 'mcl_itemframes:item_frame' },
+})