diff --git a/pyqtgraph/multiprocess/__init__.py b/pyqtgraph/multiprocess/__init__.py
index 843b42a3..32a250cb 100644
--- a/pyqtgraph/multiprocess/__init__.py
+++ b/pyqtgraph/multiprocess/__init__.py
@@ -21,4 +21,4 @@ TODO:
 
 from .processes import *
 from .parallelizer import Parallelize, CanceledError
-from .remoteproxy import proxy
\ No newline at end of file
+from .remoteproxy import proxy, ClosedError, NoResultError
diff --git a/pyqtgraph/multiprocess/bootstrap.py b/pyqtgraph/multiprocess/bootstrap.py
index bb71a703..f9cb0b0e 100644
--- a/pyqtgraph/multiprocess/bootstrap.py
+++ b/pyqtgraph/multiprocess/bootstrap.py
@@ -13,16 +13,25 @@ if __name__ == '__main__':
     #print "key:",  ' '.join([str(ord(x)) for x in authkey])
     path = opts.pop('path', None)
     if path is not None:
-        ## rewrite sys.path without assigning a new object--no idea who already has a reference to the existing list.
-        while len(sys.path) > 0:
-            sys.path.pop()
-        sys.path.extend(path)
+        if isinstance(path, str):
+            # if string, just insert this into the path
+            sys.path.insert(0, path)
+        else:
+            # if list, then replace the entire sys.path
+            ## modify sys.path in place--no idea who already has a reference to the existing list.
+            while len(sys.path) > 0:
+                sys.path.pop()
+            sys.path.extend(path)
         
     if opts.pop('pyside', False):
         import PySide
         
     
     targetStr = opts.pop('targetStr')
-    target = pickle.loads(targetStr)  ## unpickling the target should import everything we need
+    try:
+        target = pickle.loads(targetStr)  ## unpickling the target should import everything we need
+    except:
+        print("Current sys.path:", sys.path)
+        raise
     target(**opts)  ## Send all other options to the target function
     sys.exit(0)
diff --git a/pyqtgraph/multiprocess/processes.py b/pyqtgraph/multiprocess/processes.py
index 02f259e5..7560ff70 100644
--- a/pyqtgraph/multiprocess/processes.py
+++ b/pyqtgraph/multiprocess/processes.py
@@ -1,4 +1,4 @@
-import subprocess, atexit, os, sys, time, random, socket, signal
+import subprocess, atexit, os, sys, time, random, socket, signal, inspect
 import multiprocessing.connection
 try:
     import cPickle as pickle
@@ -50,7 +50,9 @@ class Process(RemoteEventHandler):
                         process to process requests from the parent process until it
                         is asked to quit. If you wish to specify a different target,
                         it must be picklable (bound methods are not).
-        copySysPath     If True, copy the contents of sys.path to the remote process
+        copySysPath     If True, copy the contents of sys.path to the remote process.
+                        If False, then only the path required to import pyqtgraph is
+                        added.
         debug           If True, print detailed information about communication
                         with the child process.
         wrapStdout      If True (default on windows) then stdout and stderr from the
@@ -82,7 +84,13 @@ class Process(RemoteEventHandler):
         port = l.address[1]
 
         ## start remote process, instruct it to run target function
-        sysPath = sys.path if copySysPath else None
+        if copySysPath:
+            sysPath = sys.path
+        else:
+            # what path do we need to make target importable?
+            mod = inspect.getmodule(target)
+            modroot = sys.modules[mod.__name__.split('.')[0]]
+            sysPath = os.path.abspath(os.path.join(os.path.dirname(modroot.__file__), '..'))
         bootstrap = os.path.abspath(os.path.join(os.path.dirname(__file__), 'bootstrap.py'))
         self.debugMsg('Starting child process (%s %s)' % (executable, bootstrap))
 
@@ -182,7 +190,8 @@ def startEventLoop(name, port, authkey, ppid, debug=False):
             HANDLER.processRequests()  # exception raised when the loop should exit
             time.sleep(0.01)
         except ClosedError:
-            break
+            HANDLER.debugMsg('Exiting server loop.')
+            sys.exit(0)
 
 
 class ForkedProcess(RemoteEventHandler):
@@ -462,21 +471,20 @@ class FileForwarder(threading.Thread):
         self.start()
 
     def run(self):
-        if self.output == 'stdout':
+        if self.output == 'stdout' and self.color is not False:
             while True:
                 line = self.input.readline()
                 with self.lock:
                     cprint.cout(self.color, line, -1)
-        elif self.output == 'stderr':
+        elif self.output == 'stderr' and self.color is not False:
             while True:
                 line = self.input.readline()
                 with self.lock:
                     cprint.cerr(self.color, line, -1)
         else:
+            if isinstance(self.output, str):
+                self.output = getattr(sys, self.output)
             while True:
                 line = self.input.readline()
                 with self.lock:
                     self.output.write(line)
-
-
-
diff --git a/pyqtgraph/multiprocess/remoteproxy.py b/pyqtgraph/multiprocess/remoteproxy.py
index 208e17f4..bc02da83 100644
--- a/pyqtgraph/multiprocess/remoteproxy.py
+++ b/pyqtgraph/multiprocess/remoteproxy.py
@@ -419,7 +419,7 @@ class RemoteEventHandler(object):
             if opts is None:
                 opts = {}
             
-            assert callSync in ['off', 'sync', 'async'], 'callSync must be one of "off", "sync", or "async"'
+            assert callSync in ['off', 'sync', 'async'], 'callSync must be one of "off", "sync", or "async" (got %r)' % callSync
             if reqId is None:
                 if callSync != 'off': ## requested return value; use the next available request ID
                     reqId = self.nextRequestId
@@ -466,10 +466,7 @@ class RemoteEventHandler(object):
             return req
             
         if callSync == 'sync':
-            try:
-                return req.result()
-            except NoResultError:
-                return req
+            return req.result()
         
     def close(self, callSync='off', noCleanup=False, **kwds):
         try:
@@ -572,6 +569,10 @@ class RemoteEventHandler(object):
             self.proxies[ref] = proxy._proxyId
     
     def deleteProxy(self, ref):
+        if self.send is None:
+            # this can happen during shutdown
+            return
+
         with self.proxyLock:
             proxyId = self.proxies.pop(ref)