Fix some missing internal crosslinks

Author: zlovatt

docs/general/application.md

@@ -329,7 +329,7 @@ The project that is currently loaded. See [Project object](project.md).
 
 #### Type
 
-Project object; read-only.
+[Project object](./project.md); read-only.
 
 ---
 
@@ -612,7 +612,7 @@ None.
 
 #### Returns
 
-A new Project object, or `null` if no new project is created.
+A new [Project object](./project.md), or `null` if no new project is created.
 
 #### Example
 
@@ -642,7 +642,7 @@ Opens a project.
 
 #### Returns
 
-A new Project object for the specified project, or `null` if the user cancels the Open dialog box.
+A new [Project object](./project.md) for the specified project, or `null` if the user cancels the Open dialog box.
 
 #### Example
 
@@ -677,7 +677,7 @@ Opens a project faster than `app.open()` by skipping some checks.
 
 #### Returns
 
-A new Project object for the specified project.
+A new [Project object](./project.md) for the specified project.
 
 #### Example
 

docs/item/folderitem.md

@@ -31,13 +31,15 @@ if (!(secondItem instanceof FolderItem)) {
 
 #### Description
 
-An ItemCollection object containing Item object that represents the top-level contents of this folder.
+An [ItemCollection object](../item/itemcollection.md) containing Item object that represents the top-level contents of this folder.
 
-Unlike the ItemCollection in the Project object, this collection contains only the top-level items in the folder. The top-level within the folder is not the same as top-level within the project. Only those items that are top-level in the root folder are also top-level in the Project.
+Unlike the ItemCollection in the [Project object](../general/project.md), this collection contains only the top-level items in the folder. The top-level within the folder is not the same as top-level within the project.
+
+Only those items that are top-level in the root folder are also top-level in the Project.
 
 #### Type
 
-ItemCollection object; read-only.
+[ItemCollection object](../item/itemcollection.md); read-only.
 
 ---
 

docs/item/itemcollection.md

@@ -4,7 +4,7 @@
 
 #### Description
 
-The ItemCollection object represents a collection of items. The ItemCollection belonging to a Project object contains all the Item objects for items in the project. The ItemCollection belonging to a FolderItem object contains all the Item objects for items in that folder.
+The ItemCollection object represents a collection of items. The ItemCollection belonging to a [Project object](../general/project.md) contains all the Item objects for items in the project. The ItemCollection belonging to a FolderItem object contains all the Item objects for items in that folder.
 
 !!! info
     ItemCollection is a subclass of [Collection object](../other/collection.md). All methods and attributes of Collection, in addition to those listed below, are available when working with ItemCollection.