To be honest I am just too lazy to read such SQL statements. I prefer plain text explanations of what such a SQL statement shall do.
Could you please briefly describe what this SQL statement is supposed to do?
On a general note, things like the CASE clauses can often be implemented as Expression transformations.
Joins can either be performed at the source DB level (using a Source Qualifier which sources more than one table / view) or be replaced by separate Source Qualifiers (each of which delivers one table / view or a join between related tables / views) and appropriate Joiner transformations (which can perform left outer joins, right outer joins, or full joins just like a SQL join).