String processName = '{process_Name}'; //name of related process

String processVersionName = '{process_version_name}'; //name of related process version

String objectId = '{object_id}'; //id of the record flow instance is running on

String cursorAssignedTo = '{assigned_to}';  //assignee value of an active cursor. 
Value depends on step assign type: if assign type is 'User' cursorAssignedTo 
will store single user id or string with coma separated user ids. If assign type
is  'Group' /  'ChatterGroup' / 'Queue' / 'Role' / 'Profile' cursorAssignedTo will 
store corresponding record Id. If assign type is 'Call Apex' cursorAssignedTo 
will store result of apex method execution (single user id, string with coma 
separated user IDs, Role/Profile/Group id ect). If step assign type is 'Field' 
cursorAssignedTo will store string value of the corresponding field or comma separated
values of multiple fields if one added multiple fields as step assignee. If assign type
is 'System' cursorAssignedTo will store string 'System'. If assign 
type is 'Variable' it will store variable value. 

String stepAssignedTo = '{assign_to}'; //assignee value of a step related to an 
active cursor. Value depends on step assign type: if step assign type  is 'User' 
stepAssignedTo will store single user id or string with coma separated user ids. 
If assign type is 'Group' / 'ChatterGroup' / 'Queue' / 'Role' / 'Profile' stepAssignedTo 
will store corresponding record Id. If assign type is field, stepAssignedTo 
will store field api name or comma separated fields api names. If assignee type is 
'Apex' it will store apex class api name. If assign type is 'System' stepAssignedTo 
will store string 'System'. If assignee type is 'Variable' stepAssignedTo will 
store variable name. 

String stepName = '{step_name}'; //name of related process step

String swimlaneName = '{swimlane_name}'; //name of swimlane related process step belongs to

List<WR_BPM__Flow_Instance_Cursor__c> = [SELECT id from WR_BPM__Flow_Instance_Cursor__c where
WR_BPM__Flow_Instance__r.WR_BPM__Flow__r.WR_BPM__Process__r.Name = :processName AND
WR_BPM__Flow_Instance__r.WR_BPM__Flow__r.Name = :processVersionName AND
WR_BPM__Flow_Instance__r.WR_BPM__Object_Id__c = :objectId AND
WR_BPM__Step_Assigned_To__c = :cursorAssignedTo AND 
WR_BPM__Step_Assign_To__c = :stepAssignedTo AND
WR_BPM__Step__r.Name = :stepName AND
WR_BPM__Swimlane__c = :swimlaneName AND
WR_BPM__Status__c = 'In Progress' AND 
WR_BPM__Flow_Instance__r.WR_BPM__Is_Active__c = true];