the sdk published on the hex-rays website matches the last "official" release of the decompiler, which is v1.1.090612 at the time of this post.
the "warezd" training version features a newer decompiler build v1.1.090909 and unfortunately there were api-changes leading to crashes when calling "hx"-api-functions.

but there's still hope:
looking at the api-dispatcher switch-table in the disassembly of hexrays.plw the following trivial fix can be proposed:

/* snip */
/// Pointer to Hex-Rays decompiler dispatcher.
/// This variable must be instantiated by the plugin. It is initialized by init_hexrays_plugin().
extern hexdsp_t *hexdsp;

/// API call numbers
enum hexcall_t
{
	unknown_begin, 
	unknown_end,   
	unknown_next,  
	unknown_prev,  
	unknown_first, 
	unknown_second,
	unknown_find,  
	unknown_insert,
	unknown_erase, 
	unknown_clear, 
	unknown_size,  
	unknown_free,  
  hx_user_cmts_begin,
  hx_user_cmts_end,
  hx_user_cmts_next,
  hx_user_cmts_prev,
/* snip */

i didn't have the time to check all 202 api-calls but above fix seems to work well - atleast the example plugins load and do work as far as my quick testing goes ...

cheers,

dirkmill