today I want to leave a short notice on how to join few customizations into one. Basically all you need is publish customizations you want to have merged, and then on Customization Projects form ( SM204500 ) click on button View Published and then click on Download package. In that way you'll get Customization.zip which will be merged result of published customizations.
today I want to continue few more details about customization internals. In one of my long time ago posts I've described how to create customization file by yourself without Acumatica engine.
Today I want a bit extend my comment with few more details.
Quite often it is needed to add sql code to your customization. How to do it? Acumatica customizations allows it with usage of projext.xml file.
Take a loot at following example:
<Customization level="0" description="">
<File AppRelativePath="Bin\Blablabla.Acumatica.dll" FileID="d701b330-7c72-4f51-b1ae-75c4e2c02194" />
<File AppRelativePath="Pages\AP\AP306010.aspx" FileID="b9e88968-7f36-4cfc-9383-caed8363c269" />
<File AppRelativePath="Pages\AP\AP306010.aspx.cs" FileID="a1ce1918-f569-4ced-8a03-b5571dc26abb" />
if COL_LENGTH('APRegister','UsrAllocated') is null
ALTER TABLE APRegister add UsrAllocated bit default (1) WITH VALUES
if COL_LENGTH('APRegister','UsrSkipped') is null
ALTER TABLE APRegister add UsrPOSkipped bit default (1) WITH VALUES
demostrated code will create new pages AP306010.aspx, and also will modify tables APRegister with adding there columns UsrAllocated and UsrSkipped.
Take into account also that sql statement with balues will insert in all records value 1 ( due te statement bit default(1) )